SUMMARY STATEMENT 425 
4. Growth patterns and cycles of development adjusted to cli- 
matic limitations. 
5. Cultural patterns and management. 
What are the prospects of increasing drought resistance through 
genetic research? 
1. Improvements in drought resistance can be made but will 
be limited to inherited potentialities of available species, native 
or introduced. 
(a) Evaluation of indigenous material. 
(2) Mode of inheritance of important characters. 
(c) Intensive genetic and extensive breeding programs in 
arid environments. 
(d) Development of controlled selective environments for 
testing and evaluation. 
(e) Selection of adapted superior plants under field condi- 
tions. 
(f) Ability to survive natural conditions and special treat- 
ments. 
How can we develop a program of revegetation? 
1. Historical study of practices, past and present, and causes of 
failures. 
2. Analyze limiting micro-climatic factors in environment at 
representative stations. 
3. Collect preadapted races and evaluate basic adapted ma- 
terial. 
4. Introduce adapted foreign species and varieties. 
5. Determine cultural requirements of promising species and 
association of species. 
6. Use vegetative cover for increasing ground water recharge. 
7. Develop establishment procedures for revegetation with im- 
proved species and strains. 
8. Control grazing adjusted to plant requirements. 
g. Determine number and kind of livestock. 
10. Develop feed reserves for use during critical periods. 
