231 



tection of the soil and to make use of land that at present is unpro- 

 ductive. Black locust has been used very successfully, and is to be 

 recommended in localities which are moderately free from attacks of 

 the locust-borer. Where the supply of moisture in the subsoil is good, 

 Cottonwood or North Carolina poplar may also be suitable for planting 

 on these lands. 



PLANTING. 



The problem of establishing woodlots by forest planting was not 

 investigated, since this field has been covered for central and northern 

 Illinois by a previous publication.* However, it is sometimes desirable 

 to resort to planting in the management of timbered lands where 

 natural reproduction can not be successfully obtained or where it is 

 insufficient in quantity or quality. In such cases it is most important 

 that the species selected for artificial propagation be suited to the soil 

 and moisture conditions. In general, the trees listed as most valuable 

 for management in the different types will also be those which should 

 be planted. Directions for planting any of these trees may be obtained 

 by applying to the Forest Service, Washington, D. C. There is great 

 need for further experimental work in forest-planting of native and 

 introduced species in Illinois. 



GROWTH FIGURES. 



To get accurate figures on the rate of growth of trees requires a 

 more extensive and lengthy study than was practicable in view of the 



Table IX. — Growth of Swamp Spanish Oak (Quercus pagoda efolia), Illinois 



Based on sectional age counts and decade measurements of 44 trees, the stu mps 

 averaging 2.3 feet high, and ranging in age from 54 to 240 years. Measured in Wabash 

 County, IlHnois. 



* Forest Service Circular 81, Forest Planting in Illinois. 



