Effects of Differential Clipping on Growth and Development of Seedling Grasses and Legumes¹

Abstract

T HE need for proper management of forage species begins at the time of seeding and continues throughout the life of the plant. The early development of seedlings, which has a direct bearing on ultimate stands and production, is influenced to a considerable extent by time and frequency of defoliation. Very little detailed information is available on the development of young perennial grass and legume plants. Less work has been done to determine the effects of clipping on root development than on top growth. Growth of roots in successive stages of development has received little attention. This is probably largely due to the difficulty of observing closely the parts below ground. 1 Contribution from the Division of Forage Crops and Diseases, B.P.I.S.A.E. Part of a thesis submitted to the Graduate School of the University of Wisconsin in partial fulfillment of requirements for the degree of Doctor of Philosophy.

Effects of Clipping Height on Some Basic Characteristics of Timothy Grass (Phleum pratense L.)

“…Frequently and heavy clipping has a greater reducing effect on root development than above ground production (Carter andLaw 1948, Tosun 1971). These results also agree with Wagner (1952) who found that although root systems have been studied less intensively than tops, there is some evidence that the roots of forage species may be more seriously affected than the tops by certain grazing and clipping practises.…”

“…Plants cut to 2.5 cm had the lowest tiller number. Wagner (1952) and Tükel et al (1996) also found that lower clipping heights decreases the number of tiller. The other 3 cutting treatments fell within the same range for tiller number.…”

“…The above and below ground parts of plants are directly dependent upon each other for their growth and presence. As Wagner (1952) found, any change in one system has a direct bearing on its counterpart. Kacar (1983) also found that there is a strong correlation between the .…”

“…Plants with small root system are not able to produce ample forage. Root and stern are connected so vitally that any effect on either one affects the other (Wagner 1952, Kacar 1983 The use of grasses as groung cover to improve eroding land as well as a source of forage has received much attention. The amount of root material produced is an important consideration in the use of grasses for soil conservation purposes.…”

A Study of the Influence of Nitrogen on the Root Weight and Nodulation of White Clover in a Mixed Sward

“…Particularly surprising was the low weight of recoverable clover root, due in part to errors of identification, though all tap-roots were recovered. In this connection it is interesting to note the low root/top ratio of clover, 1 ; 4 as compared with 1 : 0-4--0-8 for grass; this ratio is possibly a factor of great importance in resistance to drought and to elimination under adverse conditions (27).…”