Section 14    Conversions & References

14.1 Conversions

14.1a Distance Conversions

1 inch = 25.4 millimeters
= 2.54 centimeters
1 foot = 30.48 centimeters
= 0.3048 meter
1 yard = 0.9144 meter
1 mile = 5280 feet
= 1760 yards
= 1.609 kilometers
= 1609 meters

14.1b Area Conversions

 

1 square inch = 0.0069 square feet
= 6.45 square centimeters
1 square foot = 144 square inches
= 0.11 square yard
= 0.093 square meter
1 square yard = 9 square feet
= 1296 square inches
= 0.84 square meter
1 acre = 43560 square feet
= 4840 square yards
= 4047 square meters
= 0.4047 hectares
1 hectare = 10000 square meters
= 107637 square feet
= 2.471 acres

14.1c Volume Conversions

1 cubic foot = 1728 cubic inches
= 0.037 cubic yards
= 7.481 gallons
= 28.32 liters
1 gallon = 128.0 fluid ounces
= 231.0 cubic inches
= 0.134 cubic foot
= 3782 milliliters
1 liter = 1000.0 milliliters
= 1000.0 cubic centimeters
= 2.113 pints
= 33.814 ounces
= 1.057 quarts
= 0.264 gallons
= 61.025 cubic inches
= 0.0353 cubic feet

14.1d Weight Conversions

 

1 ounce = 0.0625 pound
= 28.35 grams
1 pound = 453.6 grams
= 0.4536 kilogram
1 ton = 32000 ounces
= 2000 pounds
= 907.2 kilograms
1 kilogram = 1000 grams
= 35.27 ounces
= 2.205 pounds

14.1e Weights per Unit Area

1 ounce per 1000 ft2 = 43.56 ounces per acre
= 2.72 pounds per acre
= 1.23 kilograms per acre
= 3.05 kilograms per hectare
1 pound per 1000 ft2 = 43.56 pounds per acre
= 19.76 kilograms per acre
= 48.87 kilograms per hectare
50 pounds per 1000 ft2 = 2,178 pounds per acre
= 1.09 tons per acre
= 988 kilograms per acre
= 2443 kilograms per hectare
1 pound per acre = 0.37 ounces per 1000 ft2
= 10.41 grams per 1000 ft2
= 1.12 kilograms per hectare
50 pounds per acre = 18.37 ounces per 1000 ft2
= 1.15 pounds per 1000 ft2
= 521 grams per 1000 ft2
= 22.7 kilograms per acre
= 56.1 kilograms per hectare
1 ton per acre = 45.9 pounds per 1000 ft2
= 2242 kilograms per hectare
1 kilogram per hectare = 405 grams per acre
= 0.33 ounces per 1000 ft2
= 0.892 pounds per acre

14.1f Volumes per Unit Area

1 fluid oz. per 1000 ft2 = 2.72 pints per acre
= 1.36 quarts per acre
= 0.34 gallons per acre
= 1.29 liters per acre
= 3.18 liters per hectare
1 pint per 1000 ft2 = 16 ounces per 1000 ft2
= 43.56 pints per acre
= 21.78 quarts per acre
= 5.45 gallons per acre
= 20.6 liters per acre
= 50.9 liters per hectare
1 quart per 1000 ft2 = 32 ounces per 1000 ft2
= 2 pints per 1000 ft2
= 946 milliliters per 1000 ft2
= 43.56 quarts per acre
= 10.89 gallons per acre
= 41.2 liters per acre
= 101.9 liters per hectare
1 gallon per 1000 ft2 = 128 ounces per 1000 ft2
= 8 pints per 1000 ft2
= 4 quarts per 1000 ft2
= 3.785 liters per 1000 ft2
= 43.56 gallons per acre
= 164.9 liters per acre
= 407.4 liters per hectare
1 pint per acre = 0.37 ounces per 1000 ft2
= 0.50 quarts per acre
= 0.125 gallons per acre
= 1.17 liters per hectare
1 quart per acre = 0.73 fluid ounces per 1000 ft2
= 2 pints per acre
= 0.25 gallons per acre
= 2.34 liters per hectare
1 gallon per acre = 2.94 fluid ounces per 1000 ft2
= 9.35 liters per hectare
50 gallons per acre = 1.15 gallons per 1000 ft2
= 467.6 liters per hectare
100 gallons per acre = 2.30 gallons per 1000 ft2
= 935.3 liters per hectare

14.2 Materials Data

14.2a Construction Materials

 

Material Pounds/ foot3 Pounds/Yard3 Yards3/Ton Tons/Yard3
Clay, wet 105-120 2835-3240 0.71 - 0.62 1.42 - 1.62
Clay, dry 90-110 2430-2970 0.82 - 0.67 1.22 - 1.49
Granite 170 4590 0.44 2.30
Gravel 120-135 3240-3645 0.62 - 0.55 1.62 - 1.82
Loam, dry compact 90-100 2430-2700 0.82 - 0.74 1.22 - 1.35
Loam, dry loose 75-90 2025-2430 0.99 - 0.82 1.01 - 1.22
Sand, dry 95-110 2565-2970 0.78 - 0.67 1.28 - 1.49
Sand, wet 120-130 3240-3510 0.62 - 0.57 1.62 - 1.76
Silt, wet 130-145 3510-3915 0.57 - 0.51 1.76 - 1.96

14.2b Water Data

1 pound of water = 27.68 in3
= 0.016 ft3
1 gallon of water = 128 fluid ounces of water
= 8.34 pounds of water
= 3.785 kilograms of water
= 0.133 cubic feet (ft3) of water
= 231 cubic inches (in3) of water
= 3782 milliliters of water
1 acre inch of water = 27154 gallons of water
= 624.23 gallons of water per 1000 ft2
1 cubic foot (ft3) of water = 62.43 pounds of water
= 1728 cubic inches of water
= 0.037 cubic yards of water
= 7.481 gallons of water
= 28.32 liters of water
1 cubic yard (yd3) of water = 1713 pounds of water
1 pound per gallon of water = 120 grams per liter of water

14.3 Characteristics of Common Fertilizers

Note = The 1st number of the analysis is the percentage of nitrogen, as N. The 2nd number is the percentage of phosphorus, as P205. The 3rd number is the percentage of potassium, as K20

Fertilizer Typical Analysis Characteristics
Ammonium nitrate 33-0-0 pure white to yellowish granules, rapidly water soluble, rapidly available nitrogen, very high leaf-burn potential (salt index =102), oxidizer hazard
Ammonium sulfate 21-0-0 white, grayish, or brownish granule, rapidly water soluble, sulfur = 24%, rapidly available nitrogen, moderate leaf-burn potential (salt index = 69)
Compro 1-2-0 red-brown sewage compost (Maryland/D.C. product), high in calcium, pH is high (over pH 7.5), both rapid and slowly available nitrogen and other nutrients, moderate odor. Very low leaf burn potential but may be high in total soluble salts
Gypsum 0-0-0 off-white powder, slightly water soluble, calcium = 22%, sulfur = 19%: both slowly available, low leaf-burn potential, used as an aid to reduce soil soluble salts, and as calcium and sulfur fertilizer. Does not change soil acidity (pH)
IBDU 31-0-0 white powder or granule, slowly soluble, slowly available nitrogen, low leaf-burn potential
Leaf-gro 2-0-0 brown-black leaf compost (Maryland product), very high humus content, both rapid and slowly available nitrogen, very low leaf- burn potential, low odor
Limestone 0-0-0 off-white powder or brownish pellet, water insoluble calcium = 25-32%, magnesium = 3-12%: both slowly available, low leaf- burn potential, used to reduce soil acidity (raise pH)
Methylene urea 41-0-0 white powder or granule, slowly available nitrogen, low leaf- burn potential
Milorganite 6-2-0 brown granular sewage compost (Milwaukee product), slowly available nitrogen significant iron content, very low leaf-burn potential, moderate odor
Potassium chloride 0-0-60 red-brown or gray granule, rapidly water soluble, rapidly available potassium, high chlorine content, very high leaf-burn potential (salt index =116)
Potassium nitrate 13-0-44 white granule, rapidly water soluble, rapidly available potassium and nitrogen, oxidizer hazard, moderate leaf-burn potential (salt index = 74)
Potassium sulfate 0-50-0 grayish or pinkish granule or powder, slowly water soluble, sulfur = 18%, rapidly available potassium and sulfur, low leaf- burn potential (salt index = 46)
Sodium nitrate 16-0-0 white granule, rapidly water soluble, oxidizer hazard, high sodium content, very high leaf-burn potential salt index = 100)
Sulfur 0-0-0 yellow granule or powder, water insoluble, fire hazard, used primarily to increase soil acidity (reduce soil pH). Salt index low, but decomposes into sulfuric acid, which burns live plants
Sulfur coated urea 37-0-0 yellow granule, water insoluble, sulfur=10-12%, slowly available nitrogen and sulfur, low leaf-burn potential, reduces soil pH
Triple superphosphate 0-45-0 gray granule, water insoluble, calcium=12-14% and variable amount of sulfur, very slowly water soluble, very low leaf-burn potential (salt index = 10)
Urea 45-0-0 white granule, rapidly water soluble, rapidly available nitrogen, high leaf burn potential (salt index = 73), high volatilization-loss potential. Use of urea as de-icer pollutes groundwater!
Urea formaldehyde 38-0-0 blue granule or powder, water insoluble, slowly to very slowly available nitrogen, low leaf-burn potential

14.4 Fertilizer Application Rates

14.4a Calculations

When calculating the amount of fertilizer to apply, remember that in any fertilizer, such as 18-24-12, the first number (18) is the percent nitrogen (N), the second number (24) is the percent phosphorus (P205), and the third number (12) is the percent potassium (K20). If a fourth number is given, it is the percent sulfur (S).

For example: An 18-24-12 fertilizer contains 18% nitrogen, so for every pound of 18-24-12 that is applied, only 0.18 pound of nitrogen is actually applied. To apply 1.0 pound of nitrogen, you would need to divide 1.0 lb. N by 0.18 to get the actual amount of 18-24-12 fertilizer that contains 1.0 lb. of nitrogen: you would need 5.56 lbs. of 18-24-12 to get 1.0 lb. of nitrogen (N).

If you want to apply 1.0 lb. of N per 1000 ft2 using 18-24-12 fertilizer, you must apply 5.56 lbs. of 18-24-24. An acre has 43,560 ft2: it is 43.56 times (43.56x) bigger than 1000 ft2. To apply 1.0 lb. of N per acre, you must apply 5.56 lbs. x 43.56 = 242 lbs. of 18-24-12 fertilizer. Because a bag of fertilizer contains 50 lbs., you must divide 242 lbs. by 50 lbs. = 4.84 bags of 18-24-12.

A fertilizer such as 18-24-12 also contains phosphorus and potassium. You can calculate these by the method used above, or you can figure them as proportions of the nitrogen. Remember that 18-24-12 means 18% N and 24% P205 and 12% K20. For each pound of nitrogen, you will need 5.56 lbs. of 18-24-12, and you will also be applying 0.24 x 5.56 lbs. = 1.33 lbs. of phosphorus (P205), and 0.12 x 5.56 lbs. = .67 lbs. of potassium (K20).

14.4b Amount of Fertilizer to Apply for 0.5 lb. N and 1.0 lb. N

Note: Number of bags assumes a typical 50 pound bag weight.

. . . . . . . . . . Amount of Nitrogen Fertilizer to Apply . . . . . . . . . .

. . . . . . . . . . . . . Per Acre Basis . . . . . . . . . . . . . . . . . . . . . . . Per 1000 ft2 Basis . . . . . . . . . . .

Fertilizer 0.5 lb. N per 1000 ft2 1.0 lb. N per 1000 ft2 0.5 lb. N per 1000 ft2 1.0 lb. N per 1000 ft2
1-2-0 43.6 bags = 2,178 lbs. 87.1 bags = 4,356 lbs. 1.00 bag = 50.0 lbs. 2.00 bag = 100.0 lbs.
2-0-0 21.8 bags = 1,089 lbs. 43.6 bags = 2,178 lbs. 0.50 bag = 25.0 lbs. 1.00 bag = 50.0 lbs.
2-1-0 21.8 bags = 1,089 lbs. 43.6 bags = 2,178 lbs. 0.50 bag = 25.0 lbs. 1.00 bag = 50.0 lbs.
5-10-5 8.71 bags = 436 lbs. 17.42 bags = 871 lbs. 0.20 bag = 10.0 lbs. 0.40 bag = 20.0 lbs.
5-10-10 8.71 bags = 436 lbs. 17.42 bags = 871 lbs. 0.20 bag = 10.0 lbs. 0.40 bag = 20.0 lbs.
6-2-0 7.26 bags = 363 lbs. 14.52 bags = 726 lbs. 0.17 bag = 8.33 lbs. 0.33 lbs. = 16.7 lbs.
10-6-4 4.36 bags = 218 lbs. 8.71 bags = 436 lbs. 0.10 bag = 5.0 lbs. 0.20 bag = 10.0 lbs.
10-10-10 4.36 bags = 218 lbs. 8.71 bags = 436 lbs. 0.10 bag = 5.0 lbs. 0.20 bag = 10.0 lbs.
10-20-20 4.36 bags = 218 lbs. 8.71 bags = 436 lbs. 0.10 bag = 5.0 lbs. 0.20 bag = 10.0 lbs.
10-22-22 4.36 bags = 218 lbs. 8.71 bags = 436 lbs. 0.10 bag = 5.0 lbs. 0.20 bag = 10.0 lbs.
14-14-14 3.11 bags = 156 lbs. 6.2 bags = 311 lbs. 0.07 bags = 3.57 lbs. 0.14 bags = 7.17 lbs.
18-18-18 2.42 bags = 121 lbs. 4.84 bags = 242 lbs. 0.06 bags = 2.78 lbs. 0.11 bags = 5.56 lbs.
18-24-12 2.42 bags = 121 lbs. 4.84 bags = 242 lbs. 0.06 bags = 2.78 lbs. 0.11 bags = 5.56 lbs.
19-19-19 2.29 bags = 115 lbs. 4.59 bags = 229 lbs. 0.05 bags = 2.63 lbs. 0.11 bags = 5.26 lbs.
20-20-20 2.18 bags = 109 lbs. 4.36 bags = 218 lbs. 0.05 bags = 2.50 lbs. 0.10 bags = 5.00 lbs.
21-0-0 2.07 bags = 104 lbs. 4.15 bags = 207 lbs. 0.05 bags = 2.38 lbs. 0.10 bags = 4.76 lbs.
31-0-0 1.41 bags = 70.3 lbs. 2.81 bags = 141 lbs. 0.03 bags = 1.61 lbs. 0.06 bags = 3.23 lbs.
33-0-0 1.32 bags = 66.0 lbs. 2.64 bags = 132 lbs. 0.03 bags = 1.52 lbs. 0.06 bags = 3.03 lbs.
37-0-0 1.18 bags = 58.9 lbs. 2.35 bags = 117 lbs. 0.03 bags = 1.35 lbs. 0.05 bags = 2.70 lbs.
38-0-0 1.15 bags = 57.3 lbs. 2.29 bags = 114 lbs. 0.03 bags = 1.32 lbs. 0.05 bags = 2.63 lbs.
41-0-0 1.06 bags = 53.1 lbs. 2.12 bags = 106 lbs. 0.02 bags = 1.22 lbs. 0.05 bags = 2.44 lbs.
45-0-0 0.97 bags = 48.4 lbs. 1.94 bags = 96.8 lbs. 0.02 bags = 1.11 lbs. 0.04 bags = 2.22 lbs.
46-0-0 0.95 bags = 47.3 lbs. 1.89 bags = 94.7 lbs. 0.02 bags = 1.09 lbs. 0.04 bags = 2.17 lbs.

14.4c Amount of Fertilizer to Apply for 1.0 lb. P205 and 2.0 Lb. P205

Note: Number of bags assumes a typical 50 pound bag weight.

. . . . . . . . . . . . . . Amount of Phosphorus Fertilizer to Apply . . . . . . . . . . . .

. . . . . . . . . . . . . Per Acre Basis . . . . . . . . . . . . . . . . . . . . . . . Per 1000 ft2 Basis . . . . . . . . . . .

Fertilizer 1.0 lb. N per 1000 ft2 2.0 lb. N per 1000 ft2 1.0 lb. N per 1000 ft2 2.0 lb. N per 1000 ft2
2-1-0 87.1 bags = 4,356 lbs. 174 bags = 8,712 lbs. 2.00 bag = 100 lbs. 4.0 bags = 200 lbs.
1-2-0 43.6 bags = 2,178 lbs. 87.1 bags =4,356 lbs. 1.00 bag = 50 lbs. 2.0 bags = 100 lbs.
6-2-0 43.6 bags = 2,178 lbs. 87.1 bags =4,356 lbs. 1.00 bag = 50 lbs. 2.0 bags = 100 lbs.
10-6-4 14.5 bags = 726 lbs. 29.0 bags =1,452 lbs. 0.33 bag = 16.7 lbs. 0.66 bags = 33.3 lbs.
5-10-5 8.71 bags = 436 lbs. 17.4 bags = 871 lbs. 0.20 bag = 10.0 lbs. 0.40 bags = 20.0 lbs.
5-10-10 8.71 bags = 436 lbs. 17.4 bags = 871 lbs. 0.20 bag = 10.0 lbs. 0.40 bags = 20.0 lbs.
10-10-10 8.71 bags = 436 lbs. 17.4 bags = 871 lbs. 0.20 bag = 10.0 lbs. 0.40 bags = 20.0 lbs.
14-14-14 6.22 bags = 311 lbs. 12.4 bags = 622 lbs. 0.14 bag = 7.17 lbs 0.29 bag = 14.3 lbs.
18-18-18 4.84 bags = 242 lbs. 9.68 bags = 484 lbs. 0.11 bag = 5.56 lbs. 0.22 bag = 11.1 lbs.
19-19-19 4.59 bags = 229 lbs. 9.17 bags = 459 lbs. 0.11 bag = 5.26 lbs. 0.21 bag = 10.5 lbs.
0-20-20 4.36 bags = 218 lbs. 8.71 bags = 436 lbs. 0.10 bag = 5.00 lbs. 0.20 bag = 10.0 lbs.
10-20-20 4.36 bags = 218 lbs. 8.71 bags = 436 lbs. 0.10 bag = 5.00 lbs. 0.20 bag = 10.0 lbs.
20-20-20 4.36 bags = 218 lbs. 8.71 bags = 436 lbs. 0.10 bag = 5.00 lbs. 0.20 bag = 10.0 lbs.
10-22-22 3.96 bags = 198 lbs. 7.92 bags = 396 lbs. 0.09 bag = 4.55 lbs. 0.18 bag = 9.09 lbs.
18-24-12 3.63 bags = 182 lbs. 7.26 bags = 363 lbs. 0.08 bag = 4.17 lbs. 0.17 bag = 8.33 lbs.
0-45-0 1.94 bags = 97 lbs. 3.87 bags = 194 lbs. 0.04 bag = 2.22 lbs. 0.09 bag = 4.44 lbs.

14.5 Required Plant Nutrients

The following list describes the elemental nutrients that are required by turfgrasses and other plants. Descriptions of deficiency symptoms and the correction of plant nutrient deficiencies are included. Plants obtain all the carbon, oxygen, and hydrogen needed for growth from the air. The remaining nutrients must be obtained from the soil. The 12 most important of these nutrients are discussed below.

It is important to remember that plants require elemental nutrients in certain quantities, and that the addition of a nutrient that is already abundant in the soil will rarely improve symptoms caused by another deficient nutrient. In fact, the addition of nutrients in excess of what plants require can induce deficiencies of other elemental nutrients. Soil tests to determine which nutrients are at low (or high) levels, and to provide a basis for pH changes are essential to the correction of deficiencies.

When grass clippings are returned, and the soil pH is kept between 5.0 and 8.0, most nutrients are recycled over and over, without significant loss. Nitrogen is the exception, which over time can reach a balance in the soil that may be too low for optimum plant growth. Thus, a pH balanced soil that is well supplied with the essential nutrients can support plant growth for a long time without the addition of fertilizer.

14.5a Nitrogen

Nitrogen is part of many plant enzymes, proteins, chlorophyll, and other metabolic chemicals. Grasses that are low in nitrogen have stunted growth, yellow leaves, and early leaf death. Symptoms show up first on the oldest leaves, because plants move nitrogen from old leaves to new leaves as they grow. Plants use about as much nitrogen as they do potassium, and ten times more nitrogen than phosphorus.

Nitrogen is not part of most rocks and minerals; weathering of soil minerals releases very little nitrogen. Nitrate is the main form of nitrogen that plants use and get from soil. Although nitrate is produced in the atmosphere by lightning and combustion (e.g., air pollution), rainfall only supplies about 0.10 pound of nitrogen per 1000 ft2 per year. In nature, plants get most of their nitrogen from the decomposition of other plants and animals in the soil. Thus, nitrogen is often in short supply, and soil fertility management tends to focus on nitrogen management.

Unlike phosphorus and most other nutrients, high soil nitrogen levels are difficult to sustain. Nitrogen is lost from soils in many ways. Bacteria decompose (chemically reduce) soil nitrate and release it as nitrogen gas; this can be a problem in compact or waterlogged soils. Fertilizers and manures that contain ammonia or urea can produce ammonia gas; this can be a problem when fertilizers are left on the soil surface, or after limestone applications. Because nitrate is water soluble, it tends to move deeper into the soil where roots dont reach; this can be a management problem on sandy soils, and is a source of groundwater pollution.

Fertilizers contain different nitrogen forms, so they are used by turf managers differently. Ammonium nitrate and urea contain nitrogen that is readily used by plants; these fertilizers quickly cure nitrogen deficiency. Sulfur coated urea and urea formaldehyde release nitrogen over many months; these are maintenance fertilizers. The best way to use nitrogen fertilizer is to watch the growth of plants and keep records of application rates and times. Applying only what plants need at any given time avoids waste, expense, and environmental pollution.

14.5b Phosphorus

Phosphorus is a component of plant energy metabolism and cell membranes. Grasses which are deficient in phosphorus are usually stunted, and the leaves often develop an unusual red or purplish color. The oldest leaves are usually the first to turn purple. Plants use about as much phosphorus as they do calcium and sulfur, but they use ten times more nitrogen than they use of phosphorus.

Phosphorus is not naturally abundant in the soils of Maryland, but most agricultural lands and many residential areas have had significant phosphorus additions over the years. As a result, phosphorus deficiency is much less common than it once was, but low phosphorus levels are still frequently encountered in old forest soils, subsoils, road cuts and other disturbed sites.

Phosphorus is not easily lost from the soil because it is strongly attracted to soil particles, and does not move down through the soil with water to any significant degree. However, because most phosphorus is found in the topsoil, it can be lost whenever topsoil is lost by erosion. The loss of phosphorus due to erosion is a very significant source of groundwater pollution.

Soil pH strongly affects the ability of plants to get phosphorus from the soil. When soils are acid, so that pH is below 5.5, phosphorus forms insoluble compounds with iron and aluminum. When soils are alkaline, so that pH is above 8.0, phosphorus forms insoluble compounds with calcium and magnesium. In either case, plants can take up very little of the phosphorus which may actually be in the soil, and the addition of phosphorus fertilizer often does not result in significant improvement. When pH gets below 4.5 or above 8.5, plants can take up very little phosphorus from the soil.

14.5c Potassium

Potassium is the fluid electrolyte of plant cell sap. Just as animals use sodium as their principal fluid electrolyte, so do plants use potassium. Grasses which are deficient in potassium may be weak, brittle, or spindly. Drought tolerance, winter cold tolerance, and traffic tolerance are usually low in plants that are deficient in potassium. Leaf color is not usually seriously affected, but the edges of older leaves often become yellow and die. Plants use about as much potassium as they do nitrogen. Potassium is abundant in many soils of Maryland, but is often low in sandy soils. The availability of potassium is not very dependent on soil pH. The addition of potassium to a deficient soil usually results in long term improvement of deficiencies. The routine return of grass clippings will also keep potassium levels up.

14.5d Sulfur

Sulfur is an important component of plant structural proteins, enzymes, and chlorophyll. Sulfur, calcium, and phosphorus are used by plants in nearly equal quantities. Sulfur deficiency closely resembles nitrogen deficiency; plants are usually small and yellowish.. Most Maryland soils have adequate supplies of sulfur, and significant amounts of sulfur are added each year through acid rainfall, soils in Southern Maryland and the Eastern Shore occasionally require sulfur. Sulfur deficiency is most common where soils are sandy. The use of fertilizers which contain sulfur, such as sulfur coated urea, potassium sulfate, and ammonium sulfate are usually all that is needed to correct sulfur deficiency problems. Sulfur deficiency can also be corrected with gypsum, which also adds calcium, a plant nutrient often low in sandy soils.

14.5e Calcium

Calcium is a component of cell walls. Calcium deficient grasses have stunted growth and yellow leaves. Calcium deficiency in grasses is not common and may be difficult to distinguish from nitrogen and other deficiencies. Plants use about as much calcium as they do sulfur and phosphorus. Although calcium is usually not deficient in Maryland soils, soil pH below 5.5 makes calcium less available, and pH below 4.5 can make calcium nearly unavailable. Where soil pH is low, the addition of limestone will usually correct any calcium deficiency. In most Maryland soils, calcium is rarely low where soil pH is neutral or alkaline. Soils with a low cation exchange capacity (CEC) such as sandy soils, however, may be low in calcium with a soil pH that is only slightly acidic. Where soil calcium is low, but pH is above 6.0, the use of gypsum (calcium sulfate) is recommended. Gypsum also adds sulfur, which is often deficient in sandy soils that are low in calcium. Calcium is very important to the growth of earthworms, which have many beneficial effects on soil. The addition of calcium often results in the reduction of thatch, the reduction of soil compaction, and the improvement of water infiltration due to increases in earthworm populations.

14.5f Magnesium

Magnesium is a component of certain plant enzymes and other metabolic chemicals. Magnesium is used in fairly small quantities by plants. Magnesium deficiency is not common in grasses. Plants which are low in magnesium may have leaves that are green near the veins, but yellow over the rest of the leaf. Because plants are able to move magnesium through their tissues, magnesium deficiency usually shows up first in older leaves. Plants use about ten times more calcium than they do magnesium. The balance of calcium to magnesium in plants is important. High soil calcium levels, due to heavy applications of low-magnesium limestone, can sometimes cause magnesium deficiency; this is sometimes a problem in sandy soils. High soil magnesium levels in combination with low soil calcium levels can cause calcium deficiency; this is occasionally a problem in a band of soils derived from magnesium-rich serpentine rock which runs from western Montgomery County through northern Baltimore County. The use of dolomitic limestone for the correction of low soil pH, or where soil magnesium is low, is usually all that is needed to ensure that calcium and magnesium levels are adequate for plant growth.

14.5g Iron

Iron is a component of chlorophyll, but very small amounts are necessary for proper growth. Plants which are deficient in iron are usually yellow, sometimes almost whitish, and grow weakly. Iron is usually present in large amounts in the soil, but most of it is not in a form available to plant roots. Iron is very available at pH below 5.0, but usually is not available at pH above pH 7.5 because it forms insoluble complexes with calcium and phosphorus. Iron deficiency is occasionally caused by heavy applications of lime or phosphorus, although the effects of over-application do not usually take very long to be reversed. Because of this, it is rarely necessary to add iron to the soil, except where the amount of soil iron is actually low, which is most common in sandy soils. Because iron is absorbed by plant leaves and roots, the correction of iron deficiency is usually rapid.

14.5h Manganese

Manganese aids the function of many plant enzymes, including chlorophyll and carbohydrate metabolism. Because manganese is not very mobile in plants, deficiency symptoms usually appear first as yellow and green streaks in young leaves. Manganese is used in small quantities, but many Maryland soils are high in manganese, which can be toxic when soil pH is low (below pH 4.5). Because manganese deficiency is often associated with high soil pH, deficiencies can appear after heavy limestone applications. Plants absorb manganese from leaves and roots, so manganese deficiency can be reversed with foliar manganese applications. The reduction of soil pH and the use of a manganese micronutrient fertilizer will usually quickly correct manganese deficiency symptoms.

14.5i Boron

Boron is associated with cell development, sugar translocation, transpiration, and many enzyme systems in plants. Boron is needed in very small amounts by grasses. Boron deficiency results in slow growth, and young leaves may be twisted, stunted, and yellow; severe deficiency may kill growing points and buds,. Boron deficiency is most common on sandy soils, agricultural land where forage crops are grown, subsoils and other disturbed sites, and where soil has been over-limed to pH 7.5 to 8.0. The addition of a micronutrient fertilizer containing boron and/or correction of soil acidity to a pH below 7.0 is usually all that is required to correct boron deficiency.

14.5j Zinc

Zinc is associated with several plant enzymes. Zinc deficiency is most common where soils have high pH, or where imbalances of other micronutrients make zinc unavailable. Zinc deficiency shows up first on young leaves, which are green near the veins and yellow or white elsewhere (sometimes both the leaf veins and edges are green). Plants low in zinc may grow very slowly, with very small leaves that grow in bunches. Because zinc is absorbed through plant leaves and roots, the correction of zinc deficiency is usually rapid.

14.5k Copper

Copper is associated with several plant enzymes. Copper deficiency is not common in Maryland, but is reported where peat and other plant-derived compost has been over-applied, or where imbalances of other micronutrients make copper unavailable. Copper deficiency often resembles potassium deficiency. Plants low in copper are stunted, the oldest leaves turn yellow and may die at the edges and tips. As symptoms of copper deficiency get worse, the younger leaves may become yellow and brittle before they break off and die. Because copper is absorbed through plant leaves and roots, the correction of copper deficiency is usually rapid.

14.5l Molybdenum

Molybdenum is used in minute amounts by plants. Molybdenum deficiency is rarely reported in grasses which need very little. Molybdenum is required in greater amounts by broadleaf plants (e.g., wildflowers), and is very important to the nitrogen-fixing bacteria Rhizobia in legumes such as crown vetch and lespedeza. Molybdenum deficiency often resembles nitrogen deficiency; plants are yellow and stunted. Molybdenum deficiency is rarely reported in Maryland. Micronutrient fertilizers usually contain molybdenum as one of their ingredients.

14.6 Availability of Required Plant Nutrients By pH

The following charts show the plant availability of the various elemental plant nutrients. Note that most nutrients are abundant at pH near 6.5 (neutral), while some are abundant only at very low or very high pH, and a few have two ranges of high availability separated by a pH range of low availability.

+++++ = abundant     ++++ = very available      +++ = available     ++ = low availability      + = unavailable

Nitrogen  

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + + +
+ + + + + + + + +
+ + + + + + +
+ + + + +

Phosphorus

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + +
+ + + + + + + + +
+ + + + + + +
+ + + + + +

Potassium

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + +
+ + + + + + + + + +
+ + + + + + + + +

Sulfur

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + +
+ + + + + + + + + +
+ + + + + + + + +

Calcium

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + +
+ + + + + + + +
+ + + + +
+ + + +

Magnesium

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + +
+ + + + + + + +
+ + + + +
+ + + +

Iron

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + + +
+ + + + + + + + +
+ + + + + + +
+ + + + +

Manganese

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + +
+ + + + + + + +
+ + + + +
+ + + +

Boron

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + + +
+ + + + + + + + +
+ + + + + + + +
+ + + + + + +

Copper

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + +
+ + + + + + +
+ + + + +

Zinc

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0
+ + + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + +
+ + + + + + +
+ + + + +

14.7 Soil Test Results

14.7a Background

In addition to the University of Maryland, there are several private soil testing laboratories. Unfortunately, different soil test labs use different testing methods, and often report their analyses using different units of measurement. Although the soil test recommendations of the Maryland Cooperative Extension Service uses the same nomenclature and units as the U.M. Soil Testing Laboratory, other soil test laboratories do not.

This section shows methods which may be used to interconvert soil tests results of the University of Maryland Soil Testing Laboratory with the following laboratories: A & L Laboratories, Brookside Laboratories, and Spectrum Analytic.

The following tables were abstracted from a draft publication of the University of Maryland Cooperative Extension Service Publication (proposed publication " SFM-4").

14.7b Conversion between U.M. Soil Test Lab Pounds per Acre and Soil Fertility Index

To convert from pounds per acre of soil test nutrient to soil fertility index value, multiply pounds per acre by the value in Column 1 and then add the value in Column 2. Column 1 Column 2 To convert from soil fertility index value to pounds per acre of soil test nutrient, subtract the value in column 2 from the soil fertility index value and then divide by the value in Column 1.
P205 pounds per acre (lbs./A) 0.499 (-2.327) P fertility index value
K20 pounds per acre (lbs./A) 0.314 (-0.439) K fertility index value
Mg pounds per acre (lbs./A) 0.382 0.271 Mg fertility index value
Ca pounds per acre (lbs./A) 0.058 0.403 Ca fertility index value

14.7c Conversion between U.M. Soil Test Lab and A & L Laboratories

 

To convert from University of Maryland soil test data to an equivalent A & L Laboratories value, multiply the Maryland soil test data by the value in Column 1 and then add the value in Column 2 Column 1 Column 2 To convert from A & L Laboratories soil test data to an equivalent Univ. of Maryland value, subtract the value in Column 2 from the A & L Laboratories soil test value and then divide by the value in Column 1.
University of Maryland A & L Laboratories
P205 pounds per acre (lbs./A) 0.333 10.823 P1 (Weak Bray), ppm
K20 pounds per acre (lbs./A) 0.476 19.195 K parts per million (ppm)
Mg pounds per acre (lbs./A) 0.543 (-11.070) Mg parts per million (ppm)
Ca pounds per acre (lbs./A) 0.411 239 Ca parts per million (ppm)

14.7d Conversion between U.M. Soil Test Lab and Brookside Laboratories

 

To convert from University of Maryland soil test data to an equivalent Brookside Laboratories value, multiply the Maryland soil test data by the value in Column 1 and then add the value in Column 2 Column 1 Column 2 To convert from Brookside Laboratories soil test data to an equivalent Univ. of Maryland value, subtract the value in Column 2 from the Brookside Laboratories soil test value and then divide by the value in Column 1.
University of Maryland Brookside Laboratories
P205 pounds per acre (lbs./A) 0.445 9.504 Easily Extractable P, ppm
K20 pounds per acre (lbs./A) 0.648 9.844 K parts per million (ppm)
Mg pounds per acre (lbs./A) 0.698 4.208 Mg parts per million (ppm)
Ca pounds per acre (lbs./A) 0.523 432 Ca parts per million (ppm)

14.7e Conversion between U.M. Soil Test Lab and Spectrum Analytic

To convert from University of Maryland soil test data to an equivalent Spectrum Analytic value, multiply the Maryland soil test data by the value in Column 1 and then add the value in Column 2 Column 1 Column 2 To convert from Spectrum Analytic soil test data to an equivalent Univ. of Maryland value, subtract the value in Column 2 from the Spectrum Analytic soil test value and then divide by the value in Column 1.
University of Maryland Spectrum Analytic
P205 pounds per acre (lbs./A) 0.732 18.414 P, pounds per acre (lbs./A)
K20 pounds per acre (lbs./A) 1.022 38.322 K, pounds per acre (lbs./A)
Mg pounds per acre (lbs./A) 1.094 7.518 Mg, pounds per acre (lbs./A)
Ca pounds per acre (lbs./A) 0.758 383 Ca, pounds per acre (lbs./A)

14.8 Soil Texture Triangle

Soil Textural Triangle (Source: U.S. Dept Agriculture)

14.9 Pesticide Chart

This list is designed to serve as a handy reference guide. The MSA does not endorse or recommend any of the products included in this list, and intends no discrimination against any products which may be omitted.

Chemical Pesticide

Name Class

Common
Name

Chemical
Name
Pesticide
Class

What it Controls

Acclaim Fenoxaprop-ethyl Herbicide, postemergent grass annual & perennial warm season grasses
Alliette Fosetyl-Al Fungicide, systemic pythium diseases
Balan Benefin Herbicide, pre-emergent grass crabgrass and other annual weeds
Banner Propiconazole Fungicide, systemic dollar spot, many turf diseases
Banol Propamocarb-HCL Fungicide, systemic pythium diseases
Banvel Dicamba Herbicide, post-emergent brdlf. broadleaf weeds
Barricade Prodiamine Herbicide, pre-emergent grass crabgrass, annual bluegrass, etc.
Basagran Bentazon Herbicide, post-emergent nutsedge, some broadleaf weeds
Basamid Dazomet Herbicide, soil fumigant most live plants, seeds, soil diseases, etc.
Bayleton Triadimefon Fungicide, systemic dollar spot, many turf diseases
Benlate Benomyl Fungicide, systemic dollar spot, many turf diseases
Benomyl Benomyl Fungicide, systemic dollar spot, many turf diseases
Betasan Bensulide Herbicide, pre-emergent grass crabgrass, annual bluegrass
Buctril Bromoxynil Herbicide, post-emergent brdlf. broadleaf weeds
Caddy Cadmium chloride Fungicide, contact snow mold, most turf diseases
Calo-chlor Mercur/ous/ic Chloride Fungicide, contact snow mold, most turf diseases
Chipco 26019 Iprodione Fungicide, systemic dollar spot, most turf diseases
Cleary3336 Thiophanate-methyl Fungicide, systemic dollar spot, other turf diseases
Confront Triclopyr + Clopyralid Herbicide, post-emergent brdlf. annual and perennial broadleaf weeds
Curalan Vinclozolin Fungicide, systemic dollar spot, many turf diseases
Crusade Fonofos Insecticide, soil most insects
Cutless Flurprimidol Plant growth regulator turf growth regulator
Daconate 6 DSMA Herbicide, postemercent grass crabgrass, goosegrass, nutsedge, etc.
Daconil Chlorothalonil Fungicide, contact gray leaf spot and most turf diseases
Dacthal DCPA Herbicide, pre-emergent crabgrass, and many annual plants
Diazinon Diazinon Insecticide, contact most insects
Dithane Mancozeb Fungicide, contact dollar spot, other turf diseases
Diquat Diquat Herbicide, non-selective most plants, no soil activity
Dimension Dithiopyr Herbicide, pre-emergent grass crabgrass, other annual weeds
DSMA DSMA Herbicide, postemergent grass crabgrass, nutsedge, other annuals
Dursban Chlorpyrifos Insecticide, contact most insects
Dylox Trichlorfon Insecticide, soil  most insects
Dyrene Dyrene Fungicide, contact leaf spot, other turf diseases
Embark Mefluidide Plant growth regulator turf growth regulator
Finale Glufosinate Herbicide, non-selective most plants
Fore Mancozeb Fungicide, contact brown patch, many turf diseases
Fungo  Thiophanate-methyl Fungicide, systemic dollar spot, other turf diseases
Fusilade Fluazifop Herbicide, postemergent grass most grasses
Gallery Isoxaben Herbicide, pre-emergent brdlf. many broadleaf seedlings
Gramoxone Paraquat Herbicide, non-selective most plants
Heritage Azoxystyrobin Fungicide, systemic brown patch, other turf diseases
Lescosan Bensulide Herbicide, pre-emergent grass crabgrass, annual bluegrass
Limit Amidochlor Plant growth regulator turf growth regulator
Koban Etridiazole Fungicide, contact pythium disease
Manage Manage Herbicide, port-emergent sedge nutsedge
Mavrik Fluvalinate Insect / miticide, contact many insects, mites
Merit Imidacloprid Insecticide, systemic many insects
Mesurol Methiocarb Mulluscicide slugs and snails
Mocap Ethoprop Insect / Nematicide, soil most soil animals
Morestan Oxythioquinox Miticide, systemic mites
MSMA Monosod. Metharsonate Herbicide, post-emergent grass crabgrass, nutsedge, others
Nemacur Fenamiphos Insect / Nematicide, soil most soil animals
Oftanol Isofenphos Insecticide, soil most insects
Orthene Acephate Insecticide, systemic most insects
Paraquat Paraquat Herbicide, non-selective most plants
Pendulum Pendimethalin Herbicide, pre-emergent grass annual grass, other weeds
Pennant Metalochlor Herbicide, pre/post-emergent many annual grass weeds
Pentac Dienochlor Miticide mites
Plateau Plateau Herbicide, pre/post-emergent many grasses and broadleaf weeds
PMAS Phenylmercuric Acetate Fungicide, contact snow mold, most turf diseases
Poast Sethoxydim Herbicide, post-emergent grass most grasses
Primo Trinexapac-ethyl Plant growth regulator turf growth regulator
Pre-M Pendimethalin Herbicide, pre-emergent grass crabgrass, other annuals
Prograss Ethofumesate Herbicide, postemergent grass annual bluegrass, other grasses
Pro-Star Flutolanil Fungicide, systemic brown patch, some other turf diseases
Proxol Trichlorfon Insecticide, soil most insects
Reward Diquat Herbicide, non-selective most plants
Rodeo Glyphosate Herbicide. non-selective aquatic most aquatic plants
Ronstar Oxadiazon Herbicide, pre-emergent grass crabgrass, goosegrass, others
Roundup Glyphosate Herbicide, non-selective most plants
Rubigan Fenarimol Fungicide, systemic dollar spot, other turf diseases
Scythe Pelargonic acid Herbicide, non-selective most plants
Sentinel Cyproconazole Fungicide, systemic dollar spot, many turf diseases
Sevin Carbaryl Insecticide, contact most insects
Sevimol Carbaryl Insecticide, contact most insects
Snapshot Isoxaben Herbicide, pre-emergent brdlf. many broadleaf seedlings
Subdue Metalazyl Fungicide, systemic pythium diseases
Surflan Oryzalin Herbicide, pre-emergent grasses, other weeds
Talstar Bifenthrin Insecticide, contact many insects
Team Balan + Treflan Herbicide, pre-emergent crabgrass, other annual weeds
Telar Chlorsulfuron Herbicide, grass and broadleaf some grasses and many broadleaf
Tempo Cyfluthrin Insecticide, contact many insects
Terraneb Chloroneb Fungicide, contact pythium snow mold, other turf diseases
Terranil Chlorothalonil Fungicide, contact gray leaf spot, most turf diseases
Tersan 1991 Benomyl Fungicide, systemic dollar spot, many turf diseases
Tersan Sp Chloroneb Fungicide, contact pythium snow mold, other turf diseases
TFC Chlorsulfuron Herbicide, grass and broadleaf some grasses, many broadleaf weeds
Thalonil Chlorothalonil Fungicide, contact gray leaf spot, most turf diseases
Treflan Trifluralin Herbicide, pre-emergent crabgrass, annual seedling weeds
Trimec 2,4-D+MCPP+Dicamba Herbicide, post-emergent brdlf. broadleaf weeds
Three-Way 2,4-D+MCPP+Dicamba Herbicide, post-emergent brdlf. broadleaf weeds
Triumph Isazofos Insecticide, soil most insects
Tupersan Siduron Herbicide, pre-emergent crabgrass
Turcam Bendiocarb Insecticide, soil most insects
Turflon 2,4-D + Triclopyr Herbicide, post-emergent brdlf. broadleaf weeds
Weedone  2,4-D + MCPP Herbicide, post-emergent brdlf. broadleaf weeds

14.10 Sports Field Dimensions

14.10a Football field:

63,984 ft2 minimum playing surface and regulation boundaries
160 ft wide, plus minimum 6 ftoutside each sideline = 172 ft minimum width
300 ft long, plus 30 ft per end zone, plus minimum 6 ft outside end zones = 372 ft minimum length


14.10b Major League Baseball Field:
60,000 ft2 (approximate) minimum playing surface and regulation boundaries
320 ft minimum (350 ft preferred) foul lines, plus 60 ft behind home plate = 380 ft minimum sides
400 ft minimum home plate to outfield wall, plus 60 ft behind home plate = 460 ft minimum depth

14.10c Little League Baseball Field:

25,000 ft2 (approximate) minimum playing surface and regulation boundaries
200 ft minimum foul lines, plus 25 ft behind home plate = 225 ft minimum sides
200 ft minimum home plate to outfield wall, plus 25 ft behind home plate = 225 ft minimum depth

14.10d Softball Field (varies a lot according to league):

20,000 ft2 (approx.) to 60,000 ft2 (approx.) maximum playing surface and regulation boundaries
175 ft min (300 ft max) foul lines, plus 25 ft behind home plate = 200 ft min to 325 ft max sides
175 ft min (300 ft max) plate to wall, plus 25 ft behind plate = 200 ft min to 325 ft max depth

14.10e Soccer Field:

64,400 ft2 minimum up to 81,000 ft2 maximum playing surface
330 ft minimum (360 ft maximum) sides
195 ft minimum (225 ft maximum) sides

14.11 Seed Application Rates

14.11a General Considerations

Seed application rates are usually expressed as pounds per acre (lbs./A) or pounds per 1000 square feet (lbs./1000 ft2). These seed application rates require the assumption that the seed is 100% alive and capable of growing (germination), and also the assumption that the seed has no inert or non-seed matter included with it. Of course, this is almost never the case, since most seed lots have less than 100% germination and at least some non-seed material. Because of this, it is often convenient to think in terms of pure live seed (PLS), and to calculate seeding rates in PLS. Seeding rates specified in MSA-GS-99 are in PLS.

Some kinds of seed shatters easily from its hulls, and so are easy to clean. However, most grasses and wildflowers are classified as chaffy seed because the seed hulls, awns, and other plant parts are not easily separated from the seed at the time of cleaning. Because of this chaff, these seeds will have a higher inert matter content and thus a lower percentage of pure live seed (PLS). The maximum allowable chaff in lawn seed in Maryland is 10%, except Kentucky bluegrass seed which may be 15% chaff. The chaff must also be common to the species. Thus, soybean meal or other foreign inert matter cannot be added to lawn grass seed. There is no inert matter limitation or restriction for wildflower seed, native grass seed, and other seed.

Because seed is a viable, living product, it eventually gets old and dies. Proper seed storage is critical if seed is to survive. For most seeds, a storage temperature of 50o Fahrenheit with 50% relative humidity and low light is ideal. With proper storage, the percent germination of some seeds such as Kentucky bluegrass may actually increase during the first year of storage. However, under normal storage conditions (e.g. the back of the shop or the trailer out back, etc.) seed will begin to lose its viability, and eventually it will not germinate. This loss may take 3 to 4 years and decrease gradually (e.g., Kentucky bluegrass), or it may occur within a year and decrease quickly (e.g., chewings fescue, creeping red fescue). Having seed tested by an official laboratory is the only true way of knowing the germination.

Some native grasses and wildflower species naturally have a very low percent germination. Many legumes also have a naturally low percent germination, especially the year they are harvested. In the case of legumes and some other plants, this is due to the presence of an impermeable seed coat which prevents the seed from accepting water. Sometimes it may take several winters of freezing and thawing to crack the seed coat so that germination can occur. Such seed is referred to as hard seed. Plants sometimes also have physiological barriers to germination which must be overcome before the seed can germinate. Such seeds will not germinate until the required chemical reactions take place within the seed, which may require months or years.

Because of these factors, as well as variations caused by seasonal growing conditions and harvest timing, germination rates can be extremely variable. Thus, it is sometimes very important to calculate the percentage of pure live seed (PLS), in order to accurately determine how much seed is required for a seeding job.

14.11b Pure Live Seed (PLS) Calculation for a Single Kind / Variety

PLS is simple to calculate using the information provided on the analysis tag attached to each bag of seed sold in Maryland. To calculate PLS you need to know the percentage of pure seed and the pure seed percentage and the percent germination of the seed; both of these percentages are on the seed tag.

For example, a 50 lb. bag of Merit Kentucky bluegrass has a pure seed of 98.16% with a germination of 88%.

To calculate the PLS:

A. Multiply the % pure seed by the % germination (0.9816 x 0.88) = 86.38% PLS

To calculate the total weight of Merit PLS in a 50 lb. bag:

B. Multiply the % PLS by the net weight of the bag (0.8638 x 50) = 43.19 lbs. PLS

Thus, this 50 lb. bag of Merit Kentucky bluegrass contains 43.19 pounds of pure live seed (PLS). If the recommended seeding rate is 2.0 lbs. PLS per 1000 ft2, you will need more than 2.0 lbs. of this Merit seed.

To calculate the amount of Merit seed you will need:

C. Divide the net weight of the bag by the PLS weight of the bag (50 / 43.19) = 1.16 lbs.

D. Multiply C by the recommended seeding rate (1.16 x 2) = 2.32 lbs.

Thus, because each pound of Merit packaged in the bag is only 86% PLS, you will need 1.16 pounds of this Merit seed for each pound of PLS required by the recommended seeding rate. Since you needed two pounds of PLS, you must use 2.32 pounds of this Merit seed.

14.11c Pure Live Seed (PLS) Calculations for Mixture of Multiple Kinds / Varieties

Seed mixtures are normally sold by weight of each component that makes up the mixture. Occasionally, specifications are based on the actual pure live seed (PLS) seeding rate for each kind or variety in the mixture. Seed mixed and labeled as Maryland Interagency Certified mixtures (blue tag), or as meeting the specifications of the Maryland State Highway Administration (orange tag) must meet high standards of purity and germination. In MSA-GS-99, PLS rates are used for all seed rate recommendations. Heres how to do the math:

For example: A specification requires that 6.0 pounds of perennial ryegrass and 1.5 pounds of Kentucky bluegrass be applied per 1000 ft2. This would appear to be an 80%-20% mixture applied at 7.5 lbs./1000 ft2.

The Kentucky bluegrass and perennial ryegrass components which are chosen for this mixture show the following test results on their respective analysis tags:

 Perennial Ryegrass   99.08% pure seed   70% germination
 Kentucky Bluegrass    98.67% pure seed   95% germination

To calculate the PLS of the perennial ryegrass and Kentucky bluegrass:

Perennial Ryegrass:

A. Multiply the % pure seed by the % germination (0.9908 x 0.70) = 69.36% PLS

B. Multiply the % PLS by the required weight (0.6936 x 6.0) = 4.16 pounds

The 6.0 pounds of perennial ryegrass only contains 4.16 pounds of viable seed (PLS). Thus, to apply the recommended seeding rate of 6.0 pounds per 1000 ft2 you will need much more than 6.0 pounds of this seed:

To calculate the amount of perennial ryegrass seed you will need:

C. Divide the recommended seeding rate by the PLS weight (6.0 / 4.16) = 1.44 pounds

D. Multiply C by pounds per 1000 ft2 (1.44 x 6.0) = 8.64 pounds

Kentucky Bluegrass:

A. Multiply the % pure seed by the % germination (0.9867 x 0.95) = 93.74% PLS

B. Multiply the % PLS by the required weight (0.9374 x 1.5) = 1.41 pounds

The 1.5 pounds of Kentucky bluegrass only contains 1.41 pounds of viable seed (PLS). Thus, to apply the recommended seeding rate of 1.5 pounds per 1000 ft2 you will need more than 1.5 pounds of this seed:

To calculate the amount of Kentucky bluegrass seed you will need:

C. Divide the recommended seeding rate by the PLS weight (1.5 / 1.41) = 1.06 pounds

D. Multiply C by pounds per 1000 ft2 (1.064 x 1.5) = 1.59 pounds

To apply 6.0 pounds PLS of this perennial ryegrass seed and 1.5 pounds PLS of this Kentucky bluegrass seed you will need to mix 8.64 pounds of the perennial ryegrass and 1.59 pounds of the Kentucky bluegrass. Thus, you should not mix the seed as an 80%-20% mixture applied at 7.5 lbs./1000 ft2; instead, you should mix on the basis of an 84.46%-15.54% mixture, and seed this mix at 10.23 lbs./1000 ft2

14.12 Common and Scientific Plant Names

The following list provides both common and scientific names of the plant species mentioned in MSA Guideline Specifications 1999. Certain cultivars are included for easier recognition.

 

Species   Scientific Name   Cultivars*
*Certain cultivars are included here for recognition only; MSA does not imply any endorsement or discrimination
African daisy   Dimorphotheca aurantiaca
= Dimorphotheca sinuata

 
Alkalai grass   Puccinellia distans   Fults
American bur-reed   Sparganium americanum  
Amur honeysuckle   Lonicera maackii  
Annual bluegrass   Poa annua  
Annual gaillardia   Gaillardia pulchella  
Annual ryegrass   Lolium perenne ssp. multiflorum   Bulldog, Gulf, Magnolia
Arrow arum   Peltandra virginica  
Arrowwood viburnum Viburnum dentatum
Baby blue eyes Nemophila menziesii
Babys breath Gypsophila elegans
Bachelors button Centaurea cyanus
Baloonvine Cardiospermum halicacabrum
Bearded sedge Carex comosa
Beardtongue Penstemon digitalis
Bergamot Monarda fistulosa
Bermudagrass Cynodon dactylon Midiron, Sahara, Tufcote
Big bluestem Andropogon gerardii Bison, Champ, Niagara
Bindweed Convovulus arvensis
Birdsfoot trefoil Lotus corniculatus
= Lotus corniculatus var. arvensis
= Lotus corniculatus var. tenuifolius
Empire, Norcen, Viking
Black chokeberry Aronia melanocarpa
Black-eyed susan Rudbeckia hirta
Black haw Viburnum prunifolium
Blanketflower Gaillardia aristata
Blue flag Iris versicolor
Blue flax Linum perenne
=Linum lewisii
Blue false indigo Baptisia australis
Bluejoint grass Calamagrostis canadensis
Blue lobelia Lobelia syphilitica
Blue verbena Verbena hastata
Blue vervain Verbena hastata
Boneset Eupatorium perfoliatum
Bottlebrush grass Hystrix patula
Bristly locust Robinia fertilis
Broomsedge Andropogon virginicus
Browntop bentgrass Agrostis capillaris Highland
Buffalograss Buchloe dactyloides Bison, Buffalawn, Texoka
Bushy bluestem Andropogon glomeratus
Butterfly weed Asclepias tuberosa
Buttonbush Cephalanthus occidentalis
Calendula Calendula officinalis
Calico aster Aster lateriflorus
California poppy Eschscholzia californica
Canada bluegrass Poa compressa Canon, Reubens
Canada thistle Cirsium canadense
Canada wildrye Elymus canadensis
Canadian serviceberry Amelanchier canadensis
Cardinal flower Lobelia cardinalis
Cereal barley Hordeum vulgare Seco
Cereal oats Avena sativa
Cereal rye Secale cereale Aroostook
Cereal wheat Triticum aestivum
Chewings fescue Festuca rubra ssp. falax
= Festuca rubra
var. commutata
Jamestown, Longfellow
Clasping coneflower Rudbeckia amplexicaulis
Chickory Cicorium intybus
Clarkia Clarkia unguiculata
Cocklebur Xanthium spp.
Colonial bentgrass Agrostis tenuis Bardot, Exeter, SR-7100
Common elder Sambucus canadensis
Common three-square Scirpus americanus
Common vetch Vicia sativa
Corn cockle Agrostemma githago
Cornflower Centaurea cyanus
Corn Poppy Papaver rhoeas
Cosmos Cosmos bipinnatus
Creeping bentgrass Agrostis stolonifera
= Agrostis palustris
Penncross, Southshore, Cobra
Creeping red fescue Fescuca rubra
= Festuca rubra
ssp. rubra
Flyer, Pennlawn, Salem
Crimson clover Trifolium incarnatum
Crooked-stem aster  Aster prenanthoides
Crown vetch Coronilla varia Chemung, Penngift
Curly thistle Carduus spp.
Daisy fleabane Erigeron annuus
Dames rocket Hesperis matronalis
Deertongue Dichanthelium clandestinum
= Panicum clandestinum
Tioga
Dense blazing star Liatris spicata
Dodder Cuscuta spp.
Dwarf California poppy Eschscholzia caespitosa
Eastern gamagrass Tripsacum dactyloides
Fetterbush Leucothoe racemosa
Firewheel Gaillardia pulchella
Flat pea Lathyrus sylvestris Lathco
Flat-topped aster Aster umbellatus
Florida paspalum Paspalum floridanum
Flowering spurge Euphorbia corrollata
Forget-me-not Myosotis sylvatica
Fowl mannagrass Glyceria striata
Fox sedge Carex vulpinoidea
Foxtail millet Setaria italica
Gamagrass Tripsacum dactyloides
Gayfeather Liatris spicata
Giant bur-reed Sparganium eurycarpum
Giant foxtail Setaria faberi
Golden alexanders Zizia aurea
Golden ragwort Senecio aureus
Grass-leaved goldenrod Solidago graminifolia
= Euthamia graminifolia
Gray-headed coneflower Ratibida pinnata
Green-headed coneflower Rudbeckia laciniata
Great aster Aster grandiflorus
Great bulrush Scirpus validus
Godetia Clarkia amoena
Gold yarrow Achillea filipendulina
Hairy vetch Vicia villosa
Hairy wildrye Elymus villosus
Halberd-leaved rose mallow Hibiscus miliaris
Hard fescue Festuca trachyphylla
= Festuca longifolia
= Festuca ovina
var. duriuscula
Aurora, Reliant, Scaldis
Hard-stemmed bulrush Scirpus acutus
Heath aster Aster pilosus
Highbush blueberry Vaccinium corymbosum
Hollow joe-pye weed Eupatorium fistulosum
Hookers evening primrose Oenothera hookeri
Horse nettle Solanum carolinense
Indiangrass Sorghastrum nutans
Inkberry Ilex glabra
Italian millet Setaria italica
Joe-pye weed Eupatorium fistulosum or E. dubium
Johnsongrass Sorghum halepense
Johnny-jump-up Viola cornuta
Junegrass Koeleria cristata
= Koeleria nitida
Kentucky bluegrass Poa pratensis Baron, Merit, Monopoly
Korean lespedeza Lespedeza stipulacea
Lanceleaf coreopsis Coreopsis lanceolata
Lehmann lovegrass Eragrostis lehmanniana
Lemon mint Monarda citriodora
Little bluestem  Schizachyrium scoparium Blaze, Cimmeron
= Andropogon scoparius
Lurid sedge Carex lurida
Mallow Malva neglecta
Maltese cross Lychnis chalcedonica
Marsh hibiscus Hibiscus moscheutos
Marsh mallow Hibiscus moscheutos
Maximillian sunflower Helianthus maximilliani
Meadow fescue Festuca elatior
Mexican hat Ratibida columnifera
Milkweed Asclepias syriaca
Multiflora rose Rosa multiflora
Musk thistle Carduuus spp.
Narrow-leaved sunflower Helianthus angustifolius
Nasturtium Nasturtium officinalis
New England aster Aster novae-angliae
New York aster Aster novi-belgii
New York ironweed Vernonia noveboracensis
Orchardgrass Dactylis glomerata Hallmark
Ox-eye daisy Chrysanthemum leucanthemum
Ox-eye sunflower Heliopsis helianthoides
Partridge pea Cassia fasciculata
Perennial gaillardia Gaillardia aristata
Perennial ryegrass Lolium perenne Manhattan II, Palmer II
Pink catchfly Silene armeria
Pink Yarrow
Plains coreopsis Coreopsis tinctoria
Plumeless thistle Carduus spp.
Poison ivy Toxicodendron radicans
=Rhus radicans
Poverty oats grass Danthonia spicata
Prairie aster Machaeranthera tanacetifolia
Prairie dropseed Sporobolus heterolepis
Prairie coneflower Ratibida columnifera
Purple coneflower Echinacea purpurea
Purple loosestrife Lythrum salicaria
Purple-leaved willow-herb Epilobium coloratum
Purple lovegrass Eragrostis spectabilis
Purple-stemmed aster Aster puniceus
Purple-top Tridens flavus
= Triodia flava
Quackgrass Agropyron repens
Queen Annes lace Daucus carota
Red clover Trifolium pratense
Redtop Agrostis gigantea
= Agrostis alba
Streaker
Reed canarygrass Phalaris arundinacea Ioreed, Palaton, Rise
Rice cutgrass Leersia oryzoides
Rattlesnake-masters Eryngium yuccifolium
Rocket larkspur Delphinium ajacis
Rose mallow Hibiscus palustris or H. moscheutos
Round-headed bush-clover Lespedeza capitata
Rough-leaved goldenrod Solidago patula
Roughstalk bluegrass Poa trivialis Colt, Laser, Sabre
Scarlet flax Linum rubrum
= Linum grandiflorum rubrum
Scarlet sage Salvia coccinea
Sea oats Chasmanthium latifolium
= Uniola latifolia
Serecia lespedeza Lespedeza cuneata Appalow, Interstate
Serrated tussock Nassella trichotoma
Shasta daisy Chrysanthemum maximum
Sheep fescue Festuca ovina Azure, Bighorn, MX-86
Showy aster Aster spectabilis
Showy tick-trefoil Desmodium canadense
Shrub lespedeza Lespedeza bicolor
Siberian wallflower Cheiranthus allionii
Sicklepod Senna obtusifolia
Side-oats grama Bouteloua curtipendula
Silky dogwood Cornus amomum
Slender creeping red fescue Festuca filiformis
= Festuca tenuifolia
Dawson
Small-flowered agrimony Agrimonia parviflora
Smooth alder Alnus serrulata
Smooth aster Aster laevis
Smooth witherod Viburnum nudum
Sneezeweed Helenium autumnale
Soft rush Juncus effusus
Sorghum Sorghum halepense and hybrids
Southern arrowwood Viburnum dentatum
Spotted Joe-pye weed Eupatorium maculatum
Spotted St. Johns-wort Hypericum punctatum
Spurred anoda Anoda cristata
Spurred snapdragon Linum maroccana
Square-stemmed monkeyflower Mimulus ringens
Stiff goldenrod Solidago rigida
Sulphur cosmos Cosmos sulphureus
Swamp honeysuckle Rhododendron viscosum
Swamp milkweed Asclepias incarnata
Sweetbay magnolia Magnolia virginiana
Sweet clover Melilotus officinalis
Sweetflag Iris versicolor
Sweet goldenrod Solidago odorata
Sweet pepperbush Clethra alnifolia
Sweet william Dianthus barbatus
Sweet vernal grass Anthoxanthum odoratum
Switchgrass Panicum virgatum Alamo, Blackwell,Trailblazer
Tahoka daisy Machaeranthera tanacetifolia
Tall meadow-rue Thalictrum pubescens
Tatarian honeysuckle Lonicera tatarica
Threadleaf coreopsis Coreopsis verticillata
Three-square bulrush Scirpus americanus
Three-way sedge Dulichium arundinaceum
Timothy Phleum pratense Bounty, Glenmor, Mohawk
Tall fescue Festuca arundinacea
= Festuca elatior
var. arundinacea
Olympic II, Titan II, Rebel 3-D
Tree mallow Lavateria trimestris
Tufted hairgrass Deschampsia caespitosa
Turks-cap lily Lilium superbum
Turtlehead Chelone glabra
Velvet bentgrass Agrostis canina
Velvetgrass Holcus lanatus
Virginia mountain mint Pycnanthemum virginianum
Virginia wildrye Elymus viginicus
Violet Viola spp.
Weeping lovegrass Eragrostis curvula Morpa
White clover Trifolium repens
Whitegrass Leersia virginica
White yarrow Achillea millefolium
Wild bergamot Monarda fistulosa
Wild blue indigo Baptisia australis
Wild columbine Aquilegia canadensis
Wild garlic Allium vineale
Wild onion Allium canadense
Winterberry Ilex verticillata
Winter rye Secale cereale
Witch-hazel Hamamelis virginiana
Wrinkle-leaved goldenrod Solidago rugosa
Wood reedgrass Cinna arundinacea
Wool grass Scirpus cyperinus
Yarrow Achillea millefolium
Yellow cosmos Cosmos sulphureus
Zoysiagrass Zoysia japonica Emerald, Meyer, Zen