Ponderosa Pine in the Southwest 



351 



overs, the objective is much the same as 

 in the virgin stands, but special em- 

 phasis is placed on improving the stand 

 so as to increase growth in the younger 

 sawlog trees and the oncoming poles 

 and saplings. Residual trees that have 

 serious infections of mistletoe, have 

 been struck by lightning, or have other 

 mechanical injuries are marked for re- 

 moval. Groups are thinned by the re- 

 moval of the poorest and roughest trees. 

 After their removal, net growth takes 

 place on the best-quality stems. 



One can make intermediate light im- 

 provement-selection cuts of 300 to 600 

 board feet an acre in the old cut-overs, 

 because the stands have been made ac- 

 cessible by permanent roads. Logging 

 is done by tractors or horses, portable 

 loaders, and light trucks. As roads are 

 improved and lighter mobile equip- 

 ment is developed, it is expected that 

 stands, from which the initial harvest 

 cut has been made, will be cut over 

 every few years. By so doing, mortality 

 will be minimized, whether from wind, 

 lightning, disease, or insects, and qual- 

 ity growth will increase. Within a few 

 decades, even in areas that were heavily 

 cut 30 to 70 years ago, the net harvest- 

 able growth should be at the rate of 

 150 board feet or more an acre each 

 year. Foresters work toward that objec- 

 tive ; if they reach the goal, they will be 

 producing a large volume of excellent 

 wood in a forest that has almost the 

 characteristics of a desert in habitat 

 and moisture requirements. 



THE TREES OF THE FUTURE are the 

 seedlings, saplings, and poles, all under 

 12 inches in diameter at breast height. 

 They are found as individuals in open- 

 ings, in open stands, in dense groups, 

 or as an understory. In the Southwest, 

 young ponderosa pines are usually 

 limby if they are not growing in dense 

 stands. To produce the maximum 

 growth in quality trees for the future, 

 special attention must be given to the 

 trees of tomorrow. To that end, help 

 is given by the Knutson-Vandenberg 

 Act, under which a small part of the 

 stumpage value of the trees that are 



being sold can be used to improve the 

 timber stands. Based on an analysis of 

 each area, a decision is made as to the 

 need for improving the stand and its 

 cost. The collection of funds is pro- 

 vided for in the timber-sale agreement. 

 Most current collections vary from 25 

 cents to a dollar a thousand board feet. 



Research experiments and tests have 

 indicated that highest priority should 

 be given to pruning trees of small 

 sizes usually 4 to 1 1 inches in diam- 

 eter at breast height. The best saplings 

 and small poles are selected as crop 

 trees for pruning. All limbs are cut 

 flush with the bark to a height of 9 to 

 17 feet, depending on the size of the 

 stem. Not more than one-half of the 

 live limbs are removed, because it is 

 essential that a thrifty crown of ade- 

 quate size be retained. Trees with dead 

 limbs more than l l / 2 inches in diam- 

 eter are seldom pruned because of the 

 possibility of the entrance of western 

 red rot in the large wounds. The most 

 productive areas are selected first for 

 pruning. They are the best growing 

 sites and are free of mistletoe infec- 

 tions. By pruning now, while trees are 

 small, clear lumber or veneer will be 

 produced in the future, instead of low- 

 value boards with knots. 



Besides the periodic pruning of the 

 best trees, worthless, unusable trees are 

 removed by poisoning or cutting; they 

 are the rough, limby, or deformed trees 

 that occupy space and use moisture 

 that should be made available for the 

 good crop trees. 



Young stands of ponderosa pine can 

 be further improved by utilizing the 

 small stems that should be cut in peri- 

 odic thinnings. Little has been done so 

 far with them, but they are worth at- 

 tention. One possibility is to use the 

 smallest stems, 4 to 10 inches, for 

 posts and poles, which are used by the 

 tens of thousands in the Southwest. 

 They would have to be given a pre- 

 servative treatment, because untreated 

 ponderosa pine is not durable in con- 

 tact with the ground. No custom 

 treating plant exists now in the South- 

 west, but foresters are making an in- 



