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Danville, CA (petman2@yahoo.com)

Here is the results from two labs on the same sample. I took the samples, mixed them all together and then put some in each bag to each of A&L Analytical and A&L Eastern Here are the results and their recommendations. (multiply ppm by 2 to get lbs/acre)

Test #1


Organic Matter 4.6%
ENR lbs/A 121

Phosphorus 152 ppm Very High
Potassium 601 ppm Very High
Magnesium 715 ppm High
Calcium 3570 ppm Moderate
Sodium 577 ppm High
Sulfur SO4-S 512 ppm Very High
Zinc 8.8 ppm Very High
Manganese 64 ppm Very High
Iron 84 ppm Very High
Copper 2.5 ppm High
Boron 3.0 ppm Very High
Soluble Salts 1.71 ms/cm Very High

CEC 27.9 meq/100g

Percent Base Saturations
K 5.5%
Mg 21.4%
CA 64.1%
NA 9.0%

Add 70 lbs/acre Nitrogen
Add 40 lbs/acre Phosphate P2O5

Use ammonium sulfate as all or portion of N requirement to reduce pH
Apply 20-40# P2O5 as a side placement application
Sodium level is higher than desired, apply gypsum and leaching with water may be beneficial
Soluble salts is higher than desired, leaching with water should be beneficial

12/20/2007 12:11:01 AM

Danville, CA (petman2@yahoo.com)

Test #2

Second Test in ppm
Phosphorus 159 ppm
Potassium 592 ppm
Calcium 3426 ppm
Magnesium 581 ppm
Sulfur 491 ppm
Boron 3.7 ppm
Copper 3.7 ppm
Iron 87 ppm
Manganese 69 ppm
Zinc 8.7 ppm
Sodium 583 ppm
Organic Matter 3.3%
ENR lbs/acre 110

Calculated Cation Saturation

K 6.5%
CA 61.5%
MG 20.2%
H 0.0%
NA 11.5%

Calculated Cation Exchange Capacity 22.0 meq/100g
K:Mg Ratio 0.31

Add 90 lbs/acre Nitrogen
Add 40 lbs/acre P2O5
Add 40 lbs/acre K2O

Fertilizer should be split to reduce leaching losses and reduce risk of brurn. Broadcast in the bed or band all P2O5 and micronutrients and 25% to 70% of N and K2) at planting. Apply remaining in sidedress during growing season.


Note: ppm X 2 = lbs/A Soluble Salts ms/cm * 640 = ppm

12/20/2007 12:12:04 AM

Danville, CA (petman2@yahoo.com)

So how do I slam my pH of 7.7 down to 6.7 over the next several months and what else should I do? Rain will hopefully leach the salts. When should I add the N/P/K? Just before tilling the soil for planting or ..... Thanks!!

12/20/2007 12:15:33 AM

Windsor, Ontario, Canada

A change in pH (downward) can be achieved using sulfur. I use 90% granular sulfur. A 0.3 change can be obtained from 100lbs per 1000 square feet.

My pH was at 7.2, so I put 100lbs of sulfur in my 1500 sq ft patch. I dont want to make too big of a change at once, better in little steps. If you put down 200lbs per 1000 sq ft, that would get you around the 7.0-7.1 mark. I dont know if you want to put the 300-400lbs it would take, all at once. Thats a big change.

I would wait and see what some other guys say.

12/20/2007 9:35:59 AM

Picton,ON (j.vincent@xplornet.ca)

I would agree with Jorden. The quantities will vary though depending on the buffer capasity of the soil. Your Ca is not super high so you likely won't need quite as much as Jorden suggests. I would start with 75 lbs per 1000 in the spring. wait and retest next fall. Also, always take your soil tests at the same time of year. Readings can vary depending on timing

John

12/20/2007 10:39:40 PM

Danville, CA (petman2@yahoo.com)

Thanks. With the suggestion they made of additional N, if I were to put on say 300 pounds of Ammonium Sulfate which is 21% N and 24% S, this would seem to translate into 63 pounds of Nitrogen and 72 pounds of Sulfur. Seems to be a win/win in this case as I get both the needed N and the S to lower the pH. If I apply and till under now, some of the N will be gone by the time spring rolls around and would seem to work perfectly. Retest in early spring and adjust again? Or am I way off base. Not having the easiest time finding "large" quanitities of soil sulfur in my area.

Thanks

12/22/2007 11:27:08 AM

Cornwall UK.(50N 5W)300ft.

If it were my soil I would make getting rid of that sodium high priority.Applying gypsum as they suggest would be the way to go there.
There may also be some added benefit from its calcium if it were to knock some of that magnesium off its perch.(magnesium seems to be what is driving up your pH).

12/22/2007 12:35:47 PM

Danville, CA (petman2@yahoo.com)

Thank you too. I have 200 pounds of gypsum sitting in the garage waiting to go on as well. My patch this year is going to be 2500sf. Enough?

12/22/2007 12:43:04 PM

Cornwall UK.(50N 5W)300ft.

I see last year you posted a soil test result on 11/29/06 it had sodium 97 ppm and 1.7% base saturation.Was it the same patch?If it is we need to try and work out what caused the difference so it doesn't happen again.

12/22/2007 3:22:38 PM