Weeds are part of the climate change problem. Weeds contribute to desertification, lower rainfall, releases of CO2, methane and replacement of native fauna with nasty animals like Starlings and rodents. Weeds contribute to lyme disease, the drying of water wells and the siltation of our waterways. Weeds change the fire frequency from 100-500 years to months. Fireman die in grass or weed fires, not native wildland fires. Weeds create an alternate ecosystem that supports nothing, which favors more weeds and the destruction of habitat. There is nothing good about weeds, why do people worry about killing them?
Weeds have evolved for
thousands of years with us. Most of our activities favor weeds.
Disturbing the soil with tilling or disking favor weeds. Fertilizer
favors weeds. Watering favors weeds. Soil compacted by vehicles, our
ditches, pollution, and plastic favors weeds.
Those plastic weed barrier products favor weeds, our native plants have died under plastic 'mulch'. I suppose if you aired out the plastic for a month or so before using it the natives might be ok with it. Plastic Landscape fabric has not worked very well in any landscape we've seen. In the nursery we use the landscape fabric on gravel in the greenhouses, but we have to drag them out and shake them off, or sweep them off every year or so. The dirt builds up on the surface and weeds get established on top of them, weeds grow through them, weeds grow under them, lifting the plastic.
The soil-mulch interface
is where a
number of the soil building, root activities, and weed suppression
occur. Putting plastic in this interface. I cannot understand how
plastic landscape fabric can fit into an ecosystem. Weeds are
bothered by it, good plants are killed by it.
Clear plastic has been used to sterilize the soil with solar heat. It does a great job of killing most everything in the top ½ inch of soil, including the good guys that help suppress weeds. So the next year you have huge juicy weeds. Definitely don't put solid plastic around already established plants it will cook them or suffocate them. Putting the plastic down with bark or chips has been the pits! After a few years the bark breaks down and the plastic is exposed, the plastic breaks down and peels back. So, use the plastic if you like a yard of weeds, plastic pieces that look like shredded garbage bags, with unhappy or dead plants in it. Maybe an old car on blocks could complete the theme.
Cultivating favors weeds. You can control weeds with
cultivation, but it takes longer and you'll have to be more diligent.
First remove any weed you slice, shovel or hoe. Garbage bag them and
physically remove them from the scene. Leaving the debris favors more
Mowing or weed eating is not weed control. At best mowing can slow down the spread of weeds and the destruction of habitat. At worst you're spreading the weeds. The lesser of evils, weeds are bad, hand removing every weed is bad and sprays are bad. As Lou Costello said, "I've been a bad boy."
There are weed killers that kill grasses,(Fusilade, Poast), some kill thistles (Transline), some are called preemergents and they stop weeds from germinating,(Surflan, Ronstar, Gallery, etc.). Timing is important for chemical weed control. Proper use is also important. Follow the label and use only what you need. The grass killers need actively growing grasses, spray late and they do not work, or work poorly. If the weed has set seed, (finished flowering) even if it is still green, you're too late for sprays. Preemmerents work before the weeds germinate and they only last for about three months. Preemergents need at least a 1/4 inch of moisture after application. So, preemergents should go down before first rain, or at planting time.
Learn your weeds. Learn your natives. Kill the weeds. Plant the natives.
Ok. Now pick a defensible area that you think you can control, mulch and plant. If you can't do the whole area, pick a smaller area. Prioritize, be reasonable on what you can do, and budget full resources to do it well. Better to do a smaller area well expanding gradually over the whole area than a large area poorly, every year, for twenty years. It's like painting a house, use the good paint to paint a room at a time, don't dilute the gallon of paint and paint the whole house, tacky?
Work real hard to make the area look like a dream park. In a few years it will.For every weed you allow to set seed you will have thousands more weeds.
Some simple books for Native plant id.
Belzer, Thomas J.. 1984
of Southern California, Mountain Press, Missoula
Dale, Nancy; 1986, Flowering Plants, The Santa Monica Mountains Coastal & Chaparral Regions of Southern California, Capra Press, P.O. 2068, Santa Barbara, 93120
Kozloff, Eugene N., and Linda H. Beidleman. 1994 Plants of the San Francisco Bay Region. Sagen Press. Pacific Grove
This one has natives and weeds since it looks at it from a cattleman's lens. Just look up the plant on the net and find out if it's native and a high value wildlife plant before you decide to kill it.
Whitson, Tom, et.al. 1996. Weeds of the West. 5th edition, pioneer of Jackson Hole, Jackson Wyoming.
Also, if you really get into it, see if you can find a flora for your county and take a Taxonomy class.