Environmental Engineering Reference
In-Depth Information
Fig. 4.8. In hydroseeding, seeds, paper pulp and fertilizer mixed with water are
sprayed onto the soil surface from a distance.
Germination
Seeds need moisture to germinate, but the most critical time comes just
after germination, when seedlings have begun to root but have not yet
developed a root system. If adequate moisture is not available even for
several hours within this period, the entire stand may be lost. The surface
must be kept moist, in the absence of rain, by light applications of water
several times a day. After this critical period, which lasts for about 1
week, the grass-root system develops to the extent that water can be
obtained from the underlying soil. From this time, irrigation should
gradually increase in volume and decrease in frequency.
Mulching
When irrigation during the critical period after germination is not avail-
able, mulching (covering with a layer of dried or partially decomposed
plant matter) may improve the chances of success. Straw mulching is
inexpensive and provides excellent results. The rule is to spread enough
straw to cover the soil but to leave the surface somewhat visible. Straw or
another similar mulch helps to retain surface moisture. Daily rain or
