Environmental Engineering Reference
In-Depth Information
Table 5.3.
General tissue sufficiency ranges of nutrients for cynodon. Values
for other warm-season turf-grasses may differ slightly for macronutrients and
considerably for micronutrients.
Nutrient
Low
Medium
High
Percentage of tissue composition
Nitrogen
2.50-2.99
3.00-5.00
>5
Potassium
0.70-0.99
1.00-4.00
>4.00
Calcium
0.30-0.49
0.50-1.00
>1.00
Phosphorus
0.12-0.14
0.15-0.50
>0.50
Sulphur
0.12-0.14
0.15-0.50
>0.50
Magnesium
0.10-0.12
0.13-0.50
>0.50
Parts per million of tissue composition
Iron
40-49
50-350
>350
Manganese
16-24
25-300
>300
Boron
4-5
6-30
>30
Copper
3-4
5-50
>50
Source: J.B. Jones, Jr., B. Wolf and H.A. Mills (1991) Plant Analysis Handbook. Micro-Macro
Publishing, Athens, Georgia.
Nutrient Uptake
Turf-grass can obtain nutrients through root absorption from the soil
solution or by direct foliar absorption. Once absorbed, the nutrients can
move passively up through the transpiration stream or be actively trans-
ported within the plant. Passively transported nutrients dissolved in the
water travel through the xylem to the leaves. Actively transported nutri-
ents move from one cell to another to reach their final destinations.
Passive transport does not require energy from the plant. To carry out
active transport, the plant must expend some of the energy produced
during the process of respiration. Nutrients absorbed by roots are usually
transported passively upward through the xylem; those absorbed by turf
foliage are transported actively.
Most nutrients are absorbed by roots from the soil. Only occasionally
is foliar fertilization, also called foliar feeding, used to supply nutrients
through the leaves. Foliar application rates are usually smaller than those
intended for absorption through the roots, and the response of the turf is
typically faster. Foliar applications are used when nutrients are immobil-
ized in the soil (as iron is in alkaline soils) or when a quick improvement
in appearance is needed. Golf course superintendents and sports-
stadiummanagers spray nitrogen or iron solution over turf foliage shortly
