Wednesday, November 10, 2010

Old Cedar Tops

The management activities at Blue Jay Barrens are intended to initiate a pattern of change that results in a specific type of landscape. My intentions are like any other land manager. I want to use the most efficient and economical methods of achieving my goals. My obstacle as a manager is the fact that there are unknown and uncontrollable variables that greatly influence the outcome of my activities. A developer of something like a shopping mall has tested methods and detailed specifications upon which he can depend to help him arrive at his desired destination. The components of an ecological system don’t have the consistency of function found in materials such as wood, steel and concrete used to construct a building. In order to gain the knowledge I need to be successful in my efforts, I pay close attention to changes resulting from my actions and the actions taken by others prior to my arrival.

A single action can have long term ramifications. It took only seconds to cut the butt end off of a cedar log and let it drop to the ground. That small piece of log will be influencing this patch of ground for decades. I would really like to know the events likely to follow my actions on the land.

I know that shade from cedars hinders growth of prairie plants. I also know that removal of cedars increases the amount of sunlight reaching the ground and then the prairie plants flourish. What I’m not completely sure of is the method of cedar removal that I should use to get the best results. Can I just cut and leave the trees or do I have to drag them away? Tiny seedlings can be cut and left to decompose without having any influence on plant growth, but what about those big guys. Fortunately, I’ve been left with examples of what happens when you leave a large cedar to degrade on its own in the prairie. As a final effort to pull money from the land, previous owners removed as many cedar logs as they could before the property sold. The result was a collection of large cedar tops left in a wide variety of habitats. Each top is like a long running experiment for me to observe.
The most recently cut tops are over 25 years old. Cedar wood is naturally rot resistant and when piled in a loose manner, can remain for a century or more before decomposing. Each top provides a different type of microenvironment on and beneath the branches. The study of fallen cedar ecology could provide many graduate students with projects for their Masters and Doctoral work.

Tops that fall in heavily shaded areas practically sterilize the ground as they effectively block any sunlight. Dead needles typically stay on the tree for a couple of years and then fall to make a mulch on the surface of the ground. In situations where deciduous trees further add to the mulch with fallen leaves, it can take a long time for plants to once again colonize the area.

In partly shaded sites, the initial shading knocks back the vegetation, but lichens and mosses quickly colonize the area.

Vegetation growth is also inhibited when tops fall into sunny areas of existing grass. There is usually enough sunlight penetrating the edges of the fallen top to allow grass to continue growing. When the cedar needles finally fall, the grass revives and continues growth. Even in a sunny location there is an area directly beneath the old trunk that remains clear of vegetation.

Another area of concern is the proliferation of shrubs sprouting from the downed top. Birds tend to use the fallen tops for shelter and deposit a heavy load of seed beneath the branches. The shrubs then aggressively compete with the grass and have the ability to eventually spread and take over the prairie. I’ve adopted a policy of removing any cedar tops that fall in the prairies. In large grassland areas, a few clumps of shrubs might be desirable. At Blue Jay Barrens, where there are adequate shrub patches in the non-prairie areas, I think the grasslands will do best without the additional competition.

4 comments:

  1. Great what a nice post. this will help for making Cedar Trunks
    .

    ReplyDelete
  2. Sorry, Trunks. These logs were probably sold locally and would have been used for bird feeders and mail box posts. Cedar Trunks would have been nice though.

    ReplyDelete