Lesson 7 Page 2
Discover: The Way We Use Forests
After the 1930s and 40s, people began to ask, how can forests be preserved for future generations? The forestry industry changed its practices.
The industry has tried various techniques such as clear-cutting (removing all the trees in an area), burning small areas, using fertilizers for quicker growth, using herbicides to control insects, scarification (cutting a gash a tree so that it will die), and replanting trees to replace the ones cut down.
Tree planting in forested areas is reforestation.
Aforestation is planting trees in previously unforested areas.
Literacy Connection
Many people think that cutting down trees is bad, but when it is done in the right place and at the right time, it can be good. Foresters, biologists and loggers work together to manage forest habitats. A conservationist is a person who carefully manages a habitat to keep it healthy and to protect threatened species.
Having a variety of habitats—open meadows, young forests and mature forests—is beneficial for wildlife. A variety (diversity) of habitats leads to a diversity of wildlife. This maintains a careful balance of life.
Conservationists use many approaches such as harvesting some trees, but keeping alive other trees used by animals. They create a mix of tree types.
Small areas are cut in patches; larger areas are clear-cut to create an opening in the forest so sunlight can reach the forest floor. As long as large cuts are not made in on steep slopes (to cause erosion), or without considering how the species living there will be affected, they can be a good way to manage habitat. Mature forests are left nearby to provide food and shelter for wildlife while the cut area is growing back.
Environmental Connection
"What on Earth do forests have to do with fish?" If someone told you that disturbances to forests can damage fish populations, that would be a very good question to ask. Unfortunately, human impact on forests has put some species in danger, and that includes fish, too.
The bull trout is Alberta's official provincial fish. Bull trout were very numerous in Alberta streams 100 years ago, but now they are far fewer. Several factors have led to the decline of the bull trout, but one important reason this fish is threatened is past forestry practices. Bull trout need very clear streams in which to lay their eggs. Many streams in Alberta were made dirty and murky in the past by logging that occurred too close to the water. Without trees to hold soil in place, more erosion happens. Greater erosion leads to dirt flowing freely into streams when it rains. Bull trout cannot breed in the dirty water.
Thankfully, modern logging practices have improved, and many anglers "catch-and-release" bull trout now. As a result, bull trout populations in Alberta are holding steady.
Notebook: How has tree and forest use changed throughout history?
- Click here to download this activity.
- Complete the activity using the links provided (in the activity and below).
-
Save to your Trees Notebook.