Weed Control

The lesser of evils.

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?

With weeds

With more weeds

This is what happens when you remove the weeds!

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.

Forget the plastic and use more wood or rock mulch.
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 weeds.
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.

Nature abhors a vacuum. Bare ground allows for weeds. Mulch helps. The right mulch for the site suppresses weeds. But the right mulch combined with the right plants for that soil and plant community REALLY suppresses the weeds. Plants+mulch is ten times stronger than just mulch, mulch is six times stronger than bare ground. You can redeem yourself, plant back plants for the wildlife.

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.

Some simple books for Native plant id.

Belzer, Thomas J.. 1984 Roadside Plants 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.

For every weed you allow to set seed you will have thousands more weeds.

A few of the thousands of weeds. This are some of the real pains.

Some Common Weeds of California.(We're working on it, keep forgetting to get back to it, some of the pictures are ten years old.) The order is like weeds, rather random.

Sweet Alysum (Lobularia maritima) is included in many 'wildflower' mixes. Try to get rid of it and you'll hate the companies that peddle it. It is native to the Mediterranean area and east to Armenia, North into France. Sweet Alysum is an annual mustard that can cover large areas with its weedy habit, then die in midsummer.	Pineapple weed(Matricaria matricarioides, Lepidotheca suaveolens, Chamomilla suaveolens)  is related to chamomile which can also be a weed in many areas. Favors bare ground and disturbance. So mulch and /or leave area alone.
Filaree has many species, the  native ones are very tame. The non-native ones are destroying habitat all over California.. VERY hard to control. No real solutions once it takes over other than it  doesn't like  mulch.	This mess is largely Red Brome, aka, Foxtail Brome, Foxtail Chess, Foxtail Grass,(Bromus rubens, Bromus madritensis) under drought stess.
Why would anyone plant a five foot weed that seeds itself everywhere and you need a backhoe to remove? Cortaderia selloana, Pampas grass, mixed in with another nasty, Veldt Grass.
Watered Sunny areas.
Rabbitsfoot grass, Polypogon monspeliensis requires immediate hand removal if you find.	This small flowered Epilobium, Fireweed, is a very aggressive native. The fireweed with pretty flowers is much more a normal garden plant..
Common Dandelion, Taraxicum officinale is a common lawn weed.	Weedy Cudweed is slowed down by mulch and drought.
Centaurea melitensis. Tocalote is a nasty and hard to control thistle from Eurasia.
	Malva parviflora, Cheeseweed.
Without cultivation, Field Bindweed, Convolvulus arvensis, is a minor nuisance.