m1 -W oaes 
BN—29536 
Use of light within a community of plants is studied in the photosynthesis laboratory, Beltsville, Md. 
More information on the following subjects will help 
us develop better grazing and management systems: 
Prediction of herbage production and develop- 
ment of improved procedures for measuring yield. 
Evaluation of grazing systems, including defer- 
ment of pasture and range. 
Carrying capacity and quality of seeded species 
and mixtures and native range. 
Importance of grazing pressure in measuring 
herbage yields and quality. 
Changes in botanical composition of pasture and 
range under grazing. 
Integration of grazing with supplementary feed 
supplies. 
Differential grazing behavior of breeds and classes 
of livestock. 
Use of mixed animal species on pastures and 
range. 
Interrelationship of palatability, digestibility, and 
intake. 
Environmental factors, including shade and pest 
control, that influence animal performance in graz- 
ing studies. 
Research on the Physiology of Plant 
Growth and Development 
We need knowledge of the physiology of hay and 
pasture plants if we are to manage and improve our 
Nation’s grasslands intelligently. 
on the physiology of plant growth and development will 
increase the scope and value of field tests: will help us 
develop improved management practices for pasture 
and range and for green chop, silage, hay, and seed 
production; and will give us sound objectives for breed- 
ing improved forage varieties. For example, we need 
to know why results obtained in grazing and forage- 
production studies in one environment have only limited 
application in a slightly different environment. And 
we need more information on the physiological factors 
that limit vegetative development and seed production 
of grasses and legumes. 
To provide answers to these problems, we need knowl- 
More information 
edge on— 
@ Response of plants to the total environment, in- 
cluding variation in microclimatic conditions. 
®@ Characteristics of roots in mature plants. 
23 
