I've never heard of orach, but arugula is very savory.
The forest tent caterpillars are still feeding on hardwood trees and shrubs, here, but
are concentrated in the cities in this part of Minnesota. The adult moths are
attracted to lights, so the greatest numbers are in town, especially around gas
stations and other flood-lit areas. Another good reason for enjoying the dark sky.
Another Lepitdoptera species, the larch casebearer, is defoliating the tamaracks.
This exotic species was first introduced to the U.S. around 1900. Because it has no
natural population controls in this country, it can be fatal to its hosts (unlike the
forest tent caterpillar). A couple of non-native predators could be brought in, but
an intensive ecological analysis would be prudent before doing that. Introduction of
exotic species, even seemingly beneficial ones, is not something to be done
frivolously.
As we continue to import more and more timber products, the chances of bringing in new
exotic insects and diseases increases. Recent introductions include a "new" gypsy
moth and a wood boring beetle from Asia.
Is the best solution to reduce consumer demand, substitute alternative materials*,
meet our needs with locally harvested trees, or speed up the integration of a global
ecology so that we can achieve a balance once again by reducing regional or
continental diversity?
*Some wood substitutes may come at a higher ecological cost, like steel, aluminum,
concrete, plastic... others may have a lower cost, like hemp, kenaf, or surplus
agricultural waste like wheat straw... but consider the land use implications. Would
you rather have a diverse forest that is harvested once every 60-100 years, or an
agricultural field that is harvested annually?
