warm spot in lawn

michaewlewis – posted 11 July 2006 10:56

Hi, I am the groundskeeper at a wastewater plant in Oregon and am having trouble with a small part of one of the lawns that never turns green. There is a pipe, which carries 98 degree heated sludge, about 24″ below the turf which apparently is the cause of the lack of ability to grow grass there. I water the grass with plant water which has in it all kinds of stuff that plants love. It turns all of the other grass areas a very nice deep green. I water this lawn probably two hours, twice a week. What can be done to correct this problem? I have tried some fertilizer and it didn’t help much.

Thanks.

michaewlewis – posted 11 July 2006 11:29

pictures of turf:

http://www.onewayyouth.net/michael/wwtp/

easygrass – posted 12 July 2006 11:04

Hello,

Could you contact me @ ea***********@***oo.com

we would like to help fix your problem.

Grassguy – posted 12 July 2006 19:47

well, the rate of transpiration is certainly accelerated in that area. Stick a temp gauge in the dirt and measure the temp difference with the other areas of the lawn. If the temps seem OK sample the soil and see whats going on if its not the heat. If it is the heat perhaps you can dig down and install some sort of insulating barrier 2 feet down, this will leave plenty of room for root depth and percolation.

michaewlewis – posted 13 July 2006 14:22

The results for the temperature probe are as follows:The temperature for the brown spot was a high of 73.3*F in the sun and a low of 72.6*F in the shade.The temperature for the normal, green lawn was a high of 72*F in the sun and a low of 68.8*F in the shade.I checked the temperature in eight spots in the brown area and eight spots in the green area. Half of each was in the sunlight and half in the shade.

Grassguy – posted 13 July 2006 14:31

soil temp should not pose a threat then, Like I said before I’m sure there is more transpiration taking place in the area but who knows. I would extract soil samples in the brown area and the thriving area and submit them seperatly to your local county extension and see if there is anything wrong there. Otherwise all I can think of is more irrigation on the brown spot. If you where to pull a 6 inch deep core from the brown area and the same from the thriving area you may see that the brown areas soil is dry at that depth. just something to check. I’m curious as to what you find. I’m guessing since the heat is always there it has broken down the sub structure of the soil in that area and it may need ammendment.

SuperTurF – posted 13 July 2006 15:09

Is the area soaking wet?? If it is the effluient water you are using may be setting and causing a high salt index in your soil. This causes Iron to be locked up in the soil and cause chlorois(however you spell it) which causes the discoloration in the turf. You can tell this by probing the area and noticing if the soil is black. If this is the case your problem can be solved by the aplication of gypsum and cutting back on irrigation in that specific area.

michaewlewis – posted 14 July 2006 07:41

The soil is dryer in the brown area, and I do use plant effluent in this area.One of the plant operators suggested the problem might be caused by a possible leak in the pipe. If there was a leak, it would be constantly releasing methane gas, which would seep up through the soil.I’m not sure if I will be able to get any soil samples done unless I were to do them myself. Even then, it may not happen. The plant will be going through many changes in a couple years, including the removal of the pipe and it’s source. And I am the only one who really cares about whether this spot is fixed. So I might have to end up doing a lot of hit and miss trials on the area.Thanks.

Grassguy – posted 14 July 2006 16:04

does the effluent contain high levels of phosporus?

michaewlewis – posted 21 July 2006 12:22

The plant effluent does not contain much phosphorus.

cohiba – posted 26 July 2006 15:31

Is sodium a potential problem. Along with shallower roots that the rest of the lawn???

michaewlewis – posted 27 July 2006 11:01

there’s not much sodium in the effluent…..one of the operators believes that it could be a methane leak from the pipe. Is there anything you can do to neutralize this?

[This message has been edited by michaewlewis (edited 27 July 2006).]

cohiba – posted 28 July 2006 07:31

I doubt it would be a methane leak. The area would be dead in a circle. That is unless the leak were in a seam that ran the entire length of the pipe.

Was the pipe installed AFTER the rest of the soil was put in place from the original construction/grading of the area? Reason is it could be that the trench was back filled, compacted, and topped of with the soil differently from the rest of the surrounding area. This could prohibit the same root growth as the rest of the lawn and therefore make the turf unable to handle stress such as drought, heat, ect. If less topsoil is on that part of the lawn, root growth could be less as well as water holding abilities of the soil. Another thing. Is there a depression where the pipe is running, in the dead zone? If so it could be water lays in there and causes wet wilt or Pyhtium.

Grasping at straws…………

michaewlewis – posted 28 July 2006 15:58

hmmm… it is extremely possible that the pipe was dug up and replaced/fixed since the plant was built 50 years ago. And it did kind of feel like I was hitting gravel with the temperature probe. So the problem could be not enough soil, especially if there is a foot or more of gravel between the pipe and the surface…If that is the case, is replacing the entire section with fresh topsoil the next step? Or is there another way?

cohiba – posted 30 July 2006 10:22

If the pipe were installed by a contractor, chances are they packed it down with a plate tamper. The compacted gravel under the topsoil could be holding in the heat, and the gravel could be acting like a frying pan and concentrating the heat instead of dissipating the heat. The high heat could be cooking the roots at the deeper depths. You could try excavating the gravel and replacing with a topsoil that would be deep and not as compacted. This would allow for better water infiltration, and could also be beneficial for heat dispersement over a wider area.

Or, you could take out all the turf in the area, raise the whole entire area up about 8-12″ and create a nice little perennial bed over the entire area.

Just out of curiosity: Is this area the first to green up in the spring?

Just wondering………….Good Luck