52 YELLOW POPLAR IN TENNESSEE. 



in making mixtures and at least a portion of the trees in such mixtures 

 should be species, the wood of which can be profitably used when of small 

 s'ize. In establishing mixed plantations, the different species can be plant- 

 ed in separate rows, or each species can be planted so as to occupy a small 

 group. The cost of planting is cheaper when the species are separated 

 in rows, but the thinnings are easier executed when the species are sep- 

 arated in groups. The groups can be from one-half to one rod square. 



It is not necessary that the land should be plowed, but it is necessary 

 that it should be open, and that there should be no growth which will 

 smother or choke the young plants. Plantations should never be estab- 

 lished on very grassy sites or beneath thickets or shrubs. In planting 

 cut-over land, this must be kept in mind, and plantations should be only 

 on sites which are open. The growth of the seedling, however, is far 

 more rapid on good sites than on poor sites, and while it will soon over- 

 top brambles and such low shrubs in the rich soil of coves, it is likely to 

 be smothered by them in less favorable localities. Table No. 20 shows 

 the most profitable age for cutting yellow poplar in thinned planted stands, 

 and the cost per 1,000 board feet of growing the timber. The profit 

 shown is the net profit above all interest on the investment, which is 

 calculated at 5 per cent, a year, compounded. There is an additional 

 profit, which is not shown, in the increase in the value of stumpage. If 

 this should be at the rate of 3 per cent, per annum, which is one-fourth of 

 the rate of increase in price during the past 20 years, the investment would 

 earn more than 10 per cent a year, compounded, when die stand is 40 

 years or more old. 



