Research Solves Forestry Problems
Forestry is a science and, as such, those who practice it must have one thing that make scientific progress possible: the benefit of research. Every forestry problem solved by research lets forestry advance one more vital step.
Logically, therefore, research to solve problems is a major job of the Forest Service. It covers the whole forestry field, including the protection and management of forests, related rangelands, and water-sheds; utilization of forest products; and the economic aspects of forestry. The Services regional forest and range experiment stations and its Forest Products Laboratory are constantly making new forestry studies throughout the United States and announcing new forestry facts.
Redeeming the American Chestnut. Scientists have long been seeking ways of bringing back that valuable and storied tree, the American chestnut. Attacked by a blight brought in from Asia about 1900, practically all of our native chestnuts were killed. Their gaunt white skeletons are a reminder of a tree whose range extended from New England to Alabama and Louisiana. But there is a glimmer of hope. Forest Service scientists have found a few individual trees that seem to be resistant to the disease. Buds or branches from 28 of these tough survivors have been grafted to other root stocks for multiplication and the chance for further study of their resistance. Forest research may yet make the American chestnut once again tempt the palate , and also help supply the nations timber needs.
Can Lightning Fires Be Prevented? Foresters have a hard job making people careful with fire in the forests. At the same time, some of them are trying to make Nature cut down the number of fires she starts with her most powerful fire-starting weapon, lightning.
A little white cloud, peeking up over a Montana mountain, is quickly found by a mobile radar unit. It is tracked as it gets bigger and starts its journey with the winds. Finally, any lightning storm which develops in it is analyzed. This cooperative research project, known as Skyfire , has also made experiments in cloud seeding to reduce lightning occurrence. It is too early for positive conclusions, but scientists believe their findings will lead to a better preparedness and quicker attack on lightning-caused fires. Foresters may eventually be able to prevent lightning fires more easily than those caused by man.
Getting More Seed from Better Trees. Would you believe that healthy trees that have been deliberately wounded will produce more seed than undamaged trees? Thats what happened when foresters partly girdled some longleaf pines in Louisiana they produced twice as many cones as did ungirdled trees. In Montana, they tried it with five-year ponderosa pines. These experimental trees bore 26 cones as against one cone on the ungirdled control trees. In the South where slash pine is chipped for turpentine, the chipped trees produced 50 per cent more cones than comparable unchipped trees.
牛津译林版英语九上《Unit 1 Star signs》word同步测试(二)
鲁教版英语九年《Unit 10 It’s important to have a healthy lifestyle》word同步测试
牛津上海版英语九下《Chapter 3 A success story》word同步练习
牛津上海版英语九上《Chapter 7 Comic strips》word同步测试
牛津译林版英语九上《Unit 2 Colour》word同步测试(一)
牛津译林版英语九上《Unit 2 Colour》word同步测试
鲁教版英语九年《Unit 1 What would you do》word单元测试(A卷)
鲁教版英语九年《Unit 10 It’s important to have a healthy lifestyle》word同步练习
鲁教版英语九年《Unit 2 It must belong to Carla》word单元测试(1)
牛津译林版英语九上《Unit 5 Films》word同步测试(一)
牛津译林版英语九上《Unit 3 Teenage problems》word同步测试
鲁教版英语九年《Unit 12 I remember meeting all of you in Grade 6》word同步测试
牛津深圳版英语九年《Chapter 8 Two geniuse》word课堂练习
牛津沈阳版英语九下《Chapter 5 Family Lives》word同步练习
牛津译林版英语九上《Unit 4 TV programmes》word同步测试
牛津深圳版英语九年《Chapter 2 Care for hair》wrod配套练习
鲁教版英语九年《Unit 12 I remember meeting all of you in Grade 6》word知识总结与归纳
鲁教版英语九年《Unit 1 What would you do》word单元测试(3)
鲁教版英语九年《Unit 1 What would you do》word同步练习
鲁教版英语九年《Unit 1 What would you do》word单元测试(1)
牛津上海版英语九上《Chapter 3 The night of the horse》word同步测试4篇
牛津译林版英语九上《Unit 3 Teenage problems》word同步测试(一)
牛津深圳版英语九年《Chapter 4 What should I do》word单元复习重点
牛津深圳版英语九年《Chapter 1 Body language》word综合测试题
牛津深圳版英语九年《Chapter 3 Places of interest》wrod配套练习
牛津上海版英语九上《Chapter 2 Computers》word同步测试3篇
鲁教版英语九年《Unit 2 It must belong to Carla》word单元测试(2)
牛津上海版英语九下《Chapter 2 Educational visits》word同步测试
牛津深圳版英语九年《Chapter 4 What should I do》word单元练习
牛津上海版英语九下《Chapter 1 The green consumer》word同步测试
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |