Friday, April 17, 2009
Crabgrass, Dandelions, and a Dying Birch I
Front yards in our Edmonton neighbourhood are fairly uniform – grass maintained at various degrees of perfection, a spruce or two, and perhaps a white birch, mountain ash, or low growing conifer. Plantings of annuals and herbaceous perennials tend to be near the foundation or in a narrow bed along the front walkway, so that whatever isn’t shaded out by the spruce is covered with grass. Weekend mornings groan with the sound of lawnmowers. In July 2002, we managed to garner one such yard with a mature specimen of cutleaf weeping birch (Betula pendula) in the midst of a ratty expanse of crabgrass and dandelions and flanked by towering spruce.
Weeping Birch are beautiful trees, especially in the winter, but they need a lot of water. For the five years or so previous to our arrival, Edmonton had experienced a prolonged drought. When water-stressed, birch are susceptible to attack by the infamous bronze birch borer (Agrilus anxius). The larvae of this small (~10 mm) blackish beetle bore through the cambium of the tree and kill it from the top down. The bronze birch borer was happily munching away on North American birch when European colonists arrived, but the weeping birch was introduced from Europe and appears to be especially susceptible to its attack. The top metre or so of each stem of the multi-stemmed birch that we acquired was already dead and infested with beetles eating their way towards the ground. Thus, we were immediately confronted with a serious aesthetic problem in the front yard and a bit of a moral dilemma.
In the posts that follow, I will be meandering between describing the evolution of the Home Bug Garden and more spontaneous posts about what is happening at the moment. Every now and then I will have a rant about something I think is important - after all, that is really what blogs are about.