QuestionQUESTION: Last week I fertilized my lawn using the Superturf with weed control. Coincidentally or not, I now have annual bluegrass (I think) popping up everywhere. How can I be certain that it is in fact annual bluegrass? Will this ruin my lawn. My lawn still looks healty, but now has a whitish cast over the entire area. I am still not convinced that it is a weed, but everything about it tells me its poa anna. My other question is if there is any way I can get rid of the poa anna now? I think my once beautiful lawn is doomed. I know with mowing and watering only keeps the poa healty and more seed is produced, but what else can I do? This has become very frustrating since my lawn used to have carpetlike qualities and the envy of the neighborhood.
Please help.
ANSWER: ou can read about Poa annua ('Annual Bluegrass is the most common and widely distributed grassy weed in the world') here:
http://plants.usda.gov/java/profile?symbol=POAN
and here:
http://www.msuturfweeds.net/details/_/annual_bluegrass_47/
(Take a good look at the pictures down the right side of the page. Look familiar?)
Odds are you have it. Annual Bluegrass will go to seed right along the soil surface -- and for me, it's a major problem, because it's growing in a Bentgrass Lawn. The 'whitish cast' you mention is probably the silvery seed heads. It doesn't look like that much like a Weed -- like Crabgrass or Dandelions -- because it really is in the Bluegrass Genus. Just a different species. And yes, your Superturf fertilized it...
but...
Let's see what the USDA has to say about it on the Plants website mentioned above:
'Annual bluegrasses in warmer climates like the Southern U.S., do indeed perform as a typical winter annuals. These "annual" bluegrasses are classified as Poa annua var. annua L. Timm. In the northern part of the U.S. and much of Canada there are biotypes that produce seed in the spring and then continue to grow as perennials. This somewhat peskier bluegrass is termed Poa annua var. reptans (Hauskn) Timm.'
The wonderful thing about Poa Annua: IT IS AN ANNUAL!
And you know what that means, Frank. That means that no matter what variety you have, it's doomed. A one-Summer Weed. What more could you wish for?
Pre-emergents will take care of next year's crop of Poa. And the year after that. And the year after that. You'll have to be diligent about that because these seeds remain viable for years. And there are THOUSANDS of them.
The key is to make the living easy for the Fescue and
unhospitable for the Poa and all other weeds. Please check the Purdue Turgrass link on Poa for all the ways you can do that to Poa:
(www.agry.purdue.edu/turf/pubs/agry9802.htm)
Now, a word of warning here: Do NOT take their advice about using the chemical weedkiller ethofumesate to wipe out
the Poa. Ethofumesate is a chemical and you don't want to get started with those if you can help it.
Mow like crazy. The weeds must not set seed if you can help it. The low-growing Poa, you can do nothing about.
Later in the summer, and again in the spring as the Forsythia blooms in your neighborhood - do not miss this deadline - put down some Corn Gluten to interrupt the germination of all annual weed seed as well as to fertilize (the Corn Gluten is TRULY organic time release fertilizer high in Nitrogen) your Lawn.
Let's talk about mowing.
Mowing at the ideal height is a secret weapon you didn't know you had. It invigorates Grass to mow it right. Invigorated Grass is strong -- stronger than Weeds.
Weeds dislike it when you mow. When you chop off the top of a weed, it is like a kick in the shins. Mowing off the tips of your Grass is like a massage, it's great for the roots and it shakes up the Weeds . So you kill 2 birds w/ one stone when you mow correctly. Not all grass has the same preferred mowing height. You didn't mention your Grass or your Zone, so I can't confirm you are doing this right -- but write back and I'll go into it. Mowing at the right height eliminated 90 percent of the weeds in one
university study.
If I were you, I would put some Clover down. Clover injects Nitrogen into your soil. No fuss, no muss. And it's pretty and it smells sweet. In the 1950s, people used it all the time.
Fertilizing with Nitrogen -- this would have to be an Organic Nitrogen to build up the long term, slow dose Nitrogen generating microbes -- contributes to Grass vigor and eliminates many weeds.
Corn Gluten Meal stops seeds from Germinating. Iowa State discovered this by accident. Lots of things get discovered that way. Penicillin was discovered by accident.
Read 'Greenhouse Screening of Corn Gluten Meal as a Natural Control Product for Broadleaf and Grass Weeds'
(http://www.gluten.iastate.edu/pdf/grnhsechr.pdf).
This was a test conducted in 1995 at Iowa State University of how well Corn Gluten Meal keeps 22 weeds from sprouting. They found: 'CGM reduced plant survival, shoot length, and root development of all test species.'
Best results were seen against Black Nightshade, Common Lambsquarters, Creeping Bentgrass, Curly Dock, Purslane, and Redroot Pigweed. Twelve monocotyledonous species tested, including Quackgrass, Large Crabgrass and your Poa annua. The CGM was tested two ways: (1) Mixed into the top 2 1/2 centimeters of soil and (2) sprinkled over the soil surface, as you would with a spreader.
Velvetleaf and Barnyard Grass were toughest of the Weeds tested.
Researchers observed: "The efficacy of CGM for control of a particular weed ... depends on the amount of CGM applied. Broadleaf species were generally more susceptible to CGM than grasses ..."
The majority of Crabgrass plants are annuals. If you wait, they will be out of commission next year. Remember that as you stare at them this year. Too late for this year, but if you don't let them seed, and you don't let the set seeds germinate, you will hopefully see the last of them. Corn Gluten Meal applied in the spring will stop that from happening again. CGM is also a great Nitrogen fertilizer and it builds up your soil.
So cheer up, Frank. Your strong Lawn is going to look better and better.
Now there's something else I have to bring up. Your Superturf with Weed Control.
Given that this 'weed control' feature is unnecessary, let's look at some of the other things Scotts sold you with that Superturf.
Indiscriminate use of herbicides does all kinds of collateral damage to nontarget soil organisms and the birds and squirrels who eat them. Don't you like your neighborhood Birds?
Squirrels and Mice do get their share of bad press. But they both eat TONS of Weed seeds. So do those Birds. Remember that. And if you want more on the Iowa State Corn Gluten Meal -- a patented product that is licensed to private companies so they can sell it to you under their own label -- let me know, and I'm happy to send you a list of people in your area who sell it.
Keep me posted. Thanks for writing. I would appreciate your Rating me when you're done here.
---------- FOLLOW-UP ----------
QUESTION: Thanks for the info. I will have to go into the links provided and read on. Will my grass be wiped out when the annaul bluegrass dies off (I have Kentucky Bluegrass). Will the annual bluegrass die off with the approaching summer heat? I live in Connecticut and temps are already approaching the mid 80's.
AnswerFrank, your Kentucky Bluegrass is a Perennial. All you have to do is mow it and be nice to it. If your soil has Earthworms -- lucky for you, Earthworms multiply like Rabbits, so they can re-established in your yard if you can resist the use of Weapons of Mass Destruction again -- it becomes RICH and NUTRITIOUS. Earthworms are really incredible creatures. Aside from keeping Birds well fed.
Your KBG will be slipping into dormancy as the weather reaches into the 90s. That's not because it's weak. It's a natural cycle that protects it from extreme Summer heat. This is why it's called 'cool season Grass'. Let me know if you have any more questions. And thanks for your generous rating!
