about herbicides, or better yet, bring in a knowledgeable PCA to
be part of the team. Herbicides can be very effective in
restoring a site, planting densities can be lower if the proper
herbicides are use. On the other hand, the whole planting can die
and the water courses can become polluted with the wrong
herbicide on the wrong plant in the wrong area. Some herbicides
kill only grasses, some thistles and lupines, some germinating
seeds(largely weeds) and some everything. Once you get the easy
weeds controlled, the planted plants up, then the challenge is to
get rid of the problem weeds. Using herbicides also minimize soil
disturbance and is highly preferable to hoeing, tilling, scraping
or any of the other crazy things people try to do to get rid of
weeds. Remember there are good organisms in the soil that you
don't want to kill or disturb. Also don't forget there is usually
a huge seed bank of weed seeds. They will be back next year
unless you deter them with mulch or preemergents or both.
More info on herbicides and weeds.
grass and pampas grass have to be controlled!
Sometimes, not often, but sometimes,
grazing can help. If the project is hundreds of acres, and
mostly grass weeds, a hard pulse of grazing can remove a great
deal weeds and their litter. If there are any natives on the site
try to graze around them. This can be very effective in
increasing native bunch grass populations.
Hydroseeding sucks. Hydroseeding
almost never works, and usually is a weedy mess with erosion
Wildflowers, poppies and lupines can be
used to make the site pretty, but plants are usually
required. They are no competition for invasive weed species. They
also don't have very deep root systems for managing erosion.