From

Location

Message

Date Posted

Madera, CA

Can someone explain CEC, how to raise it, and how it relates to AGs?

Thank you.

10/19/2010 11:02:14 PM

Ham Lake, Minnesota

One of my favorite websites. Lots to soak up at this site;

http://www.spectrumanalytic.com/support/library/ff/CEC_BpH_and_percent_sat.htm

10/20/2010 1:09:43 PM

Rhode Island

with all the growers that frequest this site no one can answer this persons question? this is a very important part of your soil test results and a great question.

mtally CEC means CATON EXCHANGE CAPACITY. the cec represents the soils ability to take in and pass nutrients on into the plants vascular system.

i have asked my son ron wallace to explain the average caton exchange numbers, go into a bit more detail then i did and tell you how to inmprove your numbers.
pap

10/22/2010 9:12:00 AM

Mill Bay, British Columbia

Alex that is a good link, thanks for that.

Pap/Ron...what CEC range do we look for when growing AGs?

10/22/2010 11:48:19 AM

Coventry RI USA

Cation Exchange Capacity: Is the soil's ability to retain and supply nutrients. The lower the CEC, the lower amount of nutrients will be supplied to plants. A higher CEC will hold and supply more nutrients. Positively charged ions of Potassium, Calcium and Magnesium account for most of the soils cations. Sandy soils will commonly have a lower CEC ( less than 10 )Most pumpkin growers soil that is high in OM will have a CEC above 15.Soils that contain a higher amount of clay will also have a higher CEC. We usually have a CEC of 15-20. A higher CEC will also slow down the leaching of soil nutrients. The percentage base saturation of the CEC we look for is 65-70 % Calcium, 10-15% Magnesium and 7-10% potassium. You do not need to be 100% base saturated as long as the above nutrients and pH are in line. Our soil is sandy loam and we have to "beef it up" every fall and spring. Nutrient losses on our sandy soil can be serious during the summer so we tissue test every other week. To bring up your CEC do it slowly over a period of a few seasons. The worst thing you can do ( and we have done it ) is to put down more compost or manure than whats needed. Doing this will only throw off the balance of your soil and during the process of summer soil mineralization release too much nutrients at one time. I would rather "spoon feed" nutrients during the summer. Hope this helps.

Ron

10/23/2010 5:30:10 PM

Bloomington, IN

Good stuff! Thanks for posting! Brian

10/24/2010 8:29:24 PM

Brooklyn Corner, Nova Scotia

Thanks Dick and Ron, that's the kind of red meat I like chompin on.

10/24/2010 9:09:50 PM

Upa Creek, Mo

Great stuff from all of you. Thanks

Luke

10/24/2010 10:03:27 PM

Madera, CA

Thank you guys for the great replies. That's a lot of good info.

10/24/2010 10:19:56 PM

Annapolis Valley Nova Scotia

As far as organic matter goes what percentage should we be looking for with regards to cec ?

11/4/2010 5:59:06 PM

Rhode Island

10-15 percent OM is more than enough. to much organic matter contributes to foaming stumps .

11/5/2010 10:37:02 AM