Thursday, March 21, 2013

Spotting Spotted Spurge

Spotted Spurge in Lawn

You may or may not know what spotted spurge is, but chances are you have seen it in lawns and especially flowerbeds during the summer months.   Spotted spurge (Euphorbia maculata) is a summer annual broadleaf weed that is native to the eastern United States and is extremely common here in central California.

It grows very close to the ground and forms a dense mat of pinkish-red stems, deep green leaves with a purple spot in the center, and a center taproot pegging it to the ground.  The taproot may extend down as far as 24 inches! If the plant is pulled or broken, a white, milky latex-like sap will ooze out.  This sap can be irritating to some people’s skin.  Its leaves are in opposite pairs along the stems, and the flowers, stems, fruit, and leaves are covered with tiny hairs.

Spurge usually starts germinating in late March or April as the soil temperatures reach 60 degrees F, but really thrives when soils temperatures are 75-85 degrees F.  With little water and sunlight the seed will germinate successfully.  UC Extension literature states that it can produce viable seed within 5 weeks of germination, but I swear that it seems more like overnight.  A single plant can produce thousands of seeds that can germinate immediately if the conditions are right.  If you have ever pulled up spurge plants you can see the massive amounts of seed left behind on the soil surface.  Ants like to help move these around, too.  Maybe they like the shade it produces or perhaps it is a source of food for them.

Now we know when and what to look for in our search for spotted spurge, but how do we reduce its presence in our landscapes?  Culturally, we can watch for weeds in plants and soils we purchase to add to our landscape.  Try to pull, hoe, or spray plants before they have a chance to go to seed. Mulching the soil surface with 3-4 inches of bark chips can also reduce weed germination by shading the soil below and reducing the needed sunlight for germination.  Anything less than 3 inches is only cosmetic in terms of weed control.  In lawns, thin areas should be filled in with sod or reseeded and then fertilized and mowed at 2 inches or higher to increase the competitive edge over the spurge.


Pre emergent products like Amaze, Preen, or Dimension applied starting in March, will significantly reduce spurge populations through root inhibition.  Multiple applications may be needed for season-long control.  Post emergent products come in both selective (broadleaf herbicides for lawns) and non-selective types such as Roundup where sprays must be carefully directed to hit the weeds only.

Spurge will be here for years and years to come.  If you would like to know more about spurge, or other weeds that you wrestle with, you can call Weed Man at 559-266-1624 or visit our website at Fresno.WeedManUSA.com.

Friday, March 15, 2013

Please Water Your Lawn...Responsibly


It is now time to start thinking about watering your lawn, trees, shrubs, and flowers. It’s starting to warm up and you are probably seeing a few lawns showing signs of dry spots. I watered my lawn for the first time since October on March 1st. We want to strive to use our precious water resources responsibly which means not wasting it.

Broken Sprinkler --bradleygee
How do we waste water? Some people may over-water their landscape because they never shut it off during the winter months. Others may water during rainy periods. Some may have poor sprinkler coverage and water extra to help hide the weak spots. Others may not over-water, but they have sprinklers that spray driveways, walks, and city streets and water ends up in the culverts instead of the lawn. Some sprinklers are being blocked by plants and do not hit their intended targets, leaving a dry spot a few feet away, while at the same time, leaving a swampy lake at the base of the plant. Unfortunately, many homeowners turn on their irrigation clocks in March or April and turn them off in October or November with no seasonal adjustments addressing the temperature changes or the plant’s needs. Then there is the obvious geyser that is the result of broken lines, risers, or damaged sprinkler heads that roar through large quantities of water day after day until someone takes the time to fix it. These problems do not take care of themselves...really!

Okay, so where do you start. The very first day that you turn your irrigation clock to the on position, you should take the time to observe every sprinkler or emitter on every station. Note the patterns, coverage, and especially look for leaks or non-functioning heads. These need to be fixed immediately and checked periodically throughout the season. I would also recommend looking at the running time on each station to see if it is appropriate for the season and plant type. You should note if any runoff occurs and certainly make adjustments when you see the soil is too wet or too dry throughout the season. The City of Fresno and our website has information on the correct minutes per week broken down by month as a conservation guideline.

Water rates will soon climb much higher, so I would highly recommend looking at switching to more efficient smart time clocks and precision nozzles. The smart clocks and moisture sensors can help make logical seasonal adjustments to the plant’s needs and save significant amounts of water. Plants really don’t like too much water, or too little. The new lower precipitation nozzles really reduce runoff and have much higher water efficiency, especially over traditional spray nozzles.

We live in a desert and water is essential for growing plants and people. Let’s not waste it. For free assistance with sprinklers you may call the City of Fresno or Aqua Man, our new irrigation division. You can call Aqua Man at 475-7777, Weed Man at 266-1624 or check out our website at Fresno.WeedManUSA.com to find out more about irrigation or weed control.

Friday, March 1, 2013

Bermuda Grass – Is it Wonderful or a Weed?


We are all familiar with Bermuda grass.  It thrives in our Central Valley climate.  Bermuda is a strong lawn choice in the Valley as it can take the heat and tolerate moderately low levels of irrigation.  If you are trying to grow Bermuda as a lawn grass you probably like the fact that you can treat it sparingly and it will survive, or you can water, fertilize, and mow on a regular basis and it will provide you with a good looking lawn for years to come. 

Bermuda grass does have its limitations though.  It tolerates almost no shade and it goes dormant in the winter months leaving a tan landscape of dead leaves and stems. It has no ability to compete with winter weeds as it lies dormant making it a mottled mess if no measures are taken to prevent the weeds.  Bermuda is very invasive and able to mend open spots through rhizomes and stolons. Surprisingly it does not out-compete crabgrass though.  Keeping Bermuda in bounds and out of the nearby flowerbeds and the neighbor’s tall fescue lawn is a challenge as well.

A weed is a plant out of place.  This describes Bermuda when it is growing in what is supposed to be a tall fescue, bluegrass, or ryegrass lawn (or flower bed).  During the summer months Bermuda grass can progressively invade a lawn unnoticed as both the grasses are fully green.  As temperatures drop and the Bermuda becomes dormant, the realization of the damage is fully seen.  The key to managing the Bermuda population is to identify it early and take steps to suppress it with Turflon or spot-treat it with Roundup and reseed or sod. Applications should be applied to actively growing plants from April – September.  Once the Bermuda makes up more than 25% of the grass mix you can live with it and let it go, or at some point, kill off areas and start over.  Bermuda is not easy to kill once established, even with multiple applications of Roundup.

If you have a Bermuda lawn and it receives plenty of sunshine, I think it makes a great lawn. It should receive regular feeding, watering, mowing, and necessary weed control throughout the year.  If you have it and you love it, but the trees have grown and the shade is so heavy that you have more dirt than grass, it is time to change grasses or shrink the shape of the lawn to what areas are growing well.  If you have Bermuda and hate it and want tall fescue instead, you will need to apply Roundup 3-4 times over a period of 2-3 months starting in August.  After putting in the new lawn you will need to watch carefully for emerging Bermuda stolons and treat every 2-3 weeks with Turflon to suppress the Bermuda selectively. 

If you have any lawn questions please call Weed Man at 559-266-1624, visit our website at Fresno.WeedManUSA.com or check out our Facebook page at Facebook.com/fresnoweedman