How much nitrogen did I lose?

That's a common question right now, both in the Southeast and Midsouth.

In the Southeast, heavy rains hit in April. In the Midsouth, they came mostly in the first week of May.

Two Extension fertility specialists have responded to that question. Here are links to PDF files containg their comments:

• Arkansas Corn and Grain Sorghum News, 5-8. See Leo Espinoza's comments starting on page 2.
  
  
• Tennessee IPM Newsletter. See Hugh Savoy's comments starting on page 5.

- Owen Taylor

Heavy Rainfall: It's been the Delta's turn lately

Much of the Southeast endured heavy rainfall in mid April, and that disrupted fieldwork, caused severe silting and washing, leeched away nitrogen and set corn planting behind for weeks.

Now, it's the Midsouth's turn. The Delta states received heavy rainfall starting about 10 days ago. We've heard of some locations receiving 12 or more inches, and totals of 4 to 8 inches are common. Water was standing on fields on a wide basis by noon Tuesday, and rivers were flooding low-lying fields in parts of Arkansas and Tennessee.

Cotton, rice and soybean planting have mostly been put on hold. For more info, here are links to our cotton, rice and grain reports that cover the region:

AgFax: Midsouth Cotton: Delta cotton planting put on hold by heavy rains

RiceFax: Midsouth/Texas: Wet weather continues to delay, hurt rice in Midsouth, Texas

AgFax: Southern Grain: rains hamper Midsouth crop but were needed in Southeast, worm alerts issued

Subscriptions, by the way, are free to growers, crop advisers and industry personnel.

Click here to be added to our list.

-- Owen Taylor

Louisiana Rice: A Milestone Occasion

This is a big year for Louisiana’s Rice Research Station at Crowley. The facility, the nation's first research center devoted to rice, is celebrating its 100th anniversary, and the occasion will be marked by what is believed to be it’s 100th field day.

“It’s my understanding that the station held a field day that first year and, as near as we can tell, there has been a field day every year since then,” says Steve Linscombe, the station’s superintendent.

The station, like the rice industry itself, has come a long way in a century. A stream of new rice varieties have flowed from the station’s breeding program over the decades. In its recent history, the station has done pioneering work on herbicide-resistant rice varieties. Recently, it launched a hybrid rice project. It even has a webcam pointed toward a 6-acre block of rice, giving people all over the world a chance to see the crop develop.

The centennial will be celebrated on July 1 at the annual field day. Tours start at 7:30 a.m., and the main program gets underway at 10:30 a.m., with lunch following.

Spray Tips Wear Out

The most critical part of the sprayer often gets the least tender love and care. Fact is, the spray tips are quite fragile and tiny distortions to the openings of the tip can cause distorted spray patterns and product deposition.

The major problem though with spray tips is orifice wear. This was especially true when most of the spray tips were made of brass. The soft brass tips were really a problem when the spray formulation was some type dry material. Those tips did not last long. The stainless steel tips being made now are far superior. Still, there can be questionable tips that produce variations in the spray volumes and the spray patterns. These variations may cause either poor performance on the bugs or phytotoxicity to the crop being treated.

The best thing to do is use your small measuring cup and a stop watch to measure the flow from each spray tip. If the flow rate is not consistent with others on the sprayer, it should be replaced. These few minutes checking the flow rate will insure even spraying and optimum performance.

When a spray tip is clogged, please don’t use your pocket knife or a piece of small wire to clean it. You may get the tip cleaned, but you may also damage the most critical part of the tip, the opening. Use a soft brush and gently clean it. An old toothbrush will do just fine.

For additional information, you may want to refer to TeeJet.com

Take care of your spray tips. Keep them clean and properly adjusted so the spray goes where it is supposed to at the rate it is supposed to. And you get rid of your pests.

--Tom Crumby

Spray Drift Management

Spray Drift Management
Drift has been a problem for years. To some degree, all sprays can and do drift. The objective is to keep spray drift within reasonable limits, and off sensitive property. Always keep in mind that pesticides are carried along with the spray drift droplets. And quite naturally, herbicide drift is the one that is obvious and often expensive.

Unfortunately spray drift complaints often involve non-farm situations such as adjacent property owned by folks that do not want pesticides on their property. Be a good neighbor and cooperate with their wishes. You might stop by for a visit and let them know what you are doing, and why.

Spray drift is most often caused by the small droplets(less than 100 microns) within the spray cloud. These small droplets are likely to evaporate, becoming even smaller and having the potential to drift even farther.

The optimum size for the spray cloud VMD is 400 microns. VMD is an expression of the droplet sizes contained within the spray cloud. Half of the spray droplets are smaller and half of the spray droplets are larger than 400 microns. This 400 micron spray cloud contains enough droplets for adequate target plant coverage, yet produces a minimum of smaller drift prone droplets.

One technique for managing drift is the use of drift control agents. There are several types available ranging from emulsified oils to polymers. Your local ag-chemical supplier probably has one that will give you good results.

Another critical component of drift management is wind management. Excessive winds and gusty winds are often the cause of drift events. Especially when the winds are blowing toward sensitive plants. When the winds are wrong, wait. Even if “wait” means “tomorrow”.

You should also keep the spray booms as low as practical to reduce the potential for spray drift.

A lot has been covered in this blog. Perhaps we can do another and further examine some of the components of sprayer adjustment and operation. Meanwhile, you might want to pick up some literature from the spray equipment companies such as TeeJet.com. They are a great source of information, as is the Cooperative Extension Service.

In the meanwhile, keep your sprayer clean. Check your calibration frequently. And be a good neighbor by avoiding spraying when a drift incident just might be one result you did not plan on.

--Tom Crumby