Turf Green-up Underway

It has been a long winter and delayed spring this year but yesterday’s rain and that of two weekends ago has “primed the pump” and initiated new growth of many turfgrasses and other plants. Thus, there is no more time to put off yard clean-up. Any leaves, branches and other debris dropped and blown around during the winter should be removed from turfs and other lowing growing landscape plantings. Otherwise early spring growth of plants will be impeded by any debris smothering those plants.

20140330_094107 (640x360)There has been little to no leaf growth of turf to this point, so mowing isn’t needed other than for help in picking up or mulching tree leaves.

For turfs forming a complete and dense ground cover, there is no urgency to fertilize. Let the grass wake up in response to warmer weather and rain. If it is important to get the grass growing, apply low to moderate (0.25 to 0.5 lb. per 100o sq. ft.) rates of nitrogen fertilizer. Fast acting fertilizer will obviously encourage more rapid green-up. Some examples of fast acting N included ammonium sulfate, blood meal (natural organic), fish meal (natural organic), and urea. Do not apply more than 0.5 lb. per 100o sq. ft of a fast acting fertilizer at this time. Over-applying nitrogen in the spring could result in extremely fast growing grass once the weather warms into the 60 to 70 degree F range. It is also increases the risk for nitrogen leaching in locations where that is a concern.

20140405_124606 (300x169)For turfs that have poor ground cover, be aware that soil erosion will be a serious risk at this time of year. Soils are wet and easily eroded during intense spring rains. Remember that soil erosion and water runoff from bare ground can carry nitrogen and phosphate into our waterways, contributing to the eutrophication process. Take action to stabilize the soil in these areas. If turf is the intended vegetative cover, apply a seed blend or mixture containing perennial ryegrass to these areas to re-establish cover and stabilize the soil. Perennial ryegrass will germinate under cool soil temperature and is useful in re-establishing cover. If you want to delay seeding until the weather is warmer, cover these areas with a wood mulch to reduce the soil erosion and runoff that will occur during each rain.

Drought Ends in New Jersey

Last autumn I was blogging about the drought conditions that we were experiencing. Thankfully, this winter’s precipitation, albeit lots of snow, has changed our water status in the region. The U.S. Drought Monitor no longer lists New Jersey as having abnormally dry or moderate drought. You can view more details at http://www.nrcc.cornell.edu/page_drought.html

Expect I will have to post about snow mold disease and flooding, once we get a thaw.

The current drought monitor map of the Northeast.

The current drought monitor map of the Northeast.

Abnormally Dry to Moderate Drought Condition in Much of NJ

I mentioned in my previous post that dormancy has been apparent in many non-irrigated turfs. These conditions still persist throughout the central and northern NJ.

You can view the distribution and severity of the dry conditions throughout the northeastern U.S. at http://www.nrcc.cornell.edu/page_drought.htmlThis map shows that southern NJ is not experiencing drought conditions; whereas, central NJ is experiencing abnormally dry conditions, and northern NJ is experiencing moderate drought. This dryness typically doesn’t last through winter but it is something to watch. Moreover, you should assess your landscapes for any potential susceptibility to winter desiccation.

I want to share a some observations and ideas that have  come up while discussing this topic with turf managers.

  1. In those areas experiencing limited rain this fall, there has been very little recovery from summer stresses on non-irrigated turfs (and other plantings). These turfs may benefit from an application of a slow release N source to ensure recovery starts when water levels improve in late winter and early spring. Recall that NJ prohibits N applications to turf by professionals after December 1st (except on golf courses).
  2. While dry soil conditions this fall may have induced dormancy of the grass, the grass may be vulnerable to extended dryness through the winter especially in localized areas of turf that are sloped (water runs off) and exposed. These dry areas could experience desiccation damage if there are cold harsh winds combined with little to no snow or rain. If feasible, some irrigation of these areas before winter sets-in may be helpful in avoiding winter damage.
  3. Localized dry areas may have developed water repellency (become hydrophobic). These areas could benefit from an application of wetting agents to improve infiltration of rain and snow melt into the soil. Even if the soil is not hydrophobic, wetting agents will improve water infiltration of irrigation or winter precipitation.

Let’s hope that precipitation becomes more typical where it is currently dry.

Have a Happy Thanksgiving!

Dormancy in October? It is very dry and cool.

I spent a couple days this past week teaching in a turf care training program at Central Park in NYC. Many lawn areas in Central Park that are not irrigated were entering dormancy because of the dry soil conditions. And as you look around there is an increasing acreage of turf as well as shrubs and trees in our area that are being challenged by drying soil conditions. Fortunately, it is cool and many plants are tolerating the drying by entering dormant.

Lawn area entering the onset of dormancy. Shoot growth is shutting down and leaves are wilting.

However, managers should think about their end of the season programs related to irrigation shut down [Read more...]

“Rain Shadows”

Many people are aware that tree root competition is part of the challenge of maintaining turf within the drip line of trees. But the canopy of trees also contributes to the challenge by capturing and retaining much, and in some cases all, of a rain.

Rain shadows have been evident for some time now but the damage from the soil dryness has reached moderate to severe levels over the last couple weeks. Many of the lighter rainfalls over the last month haven’t wet the grass let alone the soil under large trees at Hort Farm No. 2 in North Brunswick.

The cumulative effects of a "rain shadow" and tree root competition lead to drought stress under trees.

Cleaning-up Severe Crabgrass Infestations

If you’ve experience the number of rains that we have in New Brunswick, you are probably seeing plenty of crabgrass. Weather conditions have been ideal for crabgrass in many areas of the state.

You may be asking what can be done to clean-up this weed problem [Read more...]

Green Kyllinga Found in North Brunswick

Uh-oh! We now have green kyllinga at Hort Farm No. 2 in North Brunswick. Joe Clark found it in a field that was sprayed with glyphosate. Most everything died but the kyllinga! Carrie Mansue has made some collections of kyllinga and will be doing some herbicide tests in the greenhouse this winter to determine which materials have the best activity on the this very difficult to control weed.

Keep a lookout for this weed, if left alone it will spread by rhizomes. Carrie has visited lawns that were essentially overrun by kyllinga. Once kyllinga achieves that level of dominance, control is nearly impossible without complete renovation. See previous post on the topic.

Live patch in foreground is kyllinga that survived a spray with glyphosate. Yellowed plants to left are yellow nutsedge.

Battling Green and False Kyllinga in New Jersey Turfs

We are seeing and hearing about increasing problems with green and false kyllinga; both are very troublesome invasive weed species that have moved northward into New Jersey. Green kyllinga and false green kyllinga are very similar in appearance, and both are referred to as green kyllinga. Green kyllinga is very difficult to control once large mats form.

These weeds thrive under mowing and are prolific in areas that are poorly drained or frequently wet. If you do not have [Read more...]

Tough Year for Summer Patch Disease

I have seen as much disease damage on turf this summer as any year since I began living and working in New Jersey (1991).

summer patch disease on hard fescue

Severe summer patch disease on hard fesuce at Hort Farm No. 2 in July 2013.

The hot humid weather has been ideal for summer patch and brown patch diseases.

Summer patch disease is caused by a root infecting pathogen, Magnaporthe poae. Wet weather combined with high air (soil) temperatures are thought to be very conducive to the development of summer patch disease.

I have observed more damage from summer patch disease on hard fescue turf than Kentucky bluegrass this year. This is likely due to the fact that more people are growing varieties of Kentucky bluegrass with better tolerance to this disease than was the case 20 or more years ago.

The Rutgers turfgrass breeding program is working on improving the tolerance of hard fescue to summer patch disease.

There are some cultural techniques that [Read more...]

Are there Organic Alternatives to Glyphosate?

We receive requests for information on “organic” alternatives to glyphosate (e.g., Roundup), especially for “trim” sprays on paved areas, sidewalks, skin surfaces on ball fields, etc.

The research on organic non-selective herbicides that are being marketed as replacements to glyphosate (for example, Roundup) is growing but it is much more limited that what you can find on more conventional herbicides; however, we have been evaluating some products. Our results indicate that [Read more...]