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Soil testsing in Seattle

Posted by prussell z8 WA (My Page) on
Mon, Mar 2, 09 at 15:50

I'm a little lost. Where do normal people get their soil tested around here? I need to check for petroleum residues, as well as overall quality.

Inexpensive=good. I'm affiliated with UW, too, if that's worth anything.


Follow-Up Postings:

RE: Soil testsing in Seattle

  • Posted by bboy z8 WA USA (My Page) on
    Tue, Mar 3, 09 at 2:30


Here is a link that might be useful: Soil Testing

RE: Soil testsing in Seattle

Yes, I found that. The pdf that lists soil testing agencies is currently a broken link, so that's not helpful. When it was working, there were literally dozens of companies there. I was hoping someone could give a more specific recommendation.


RE: Soil testsing in Seattle works perfectly well for me :-))

Try this - it should get you there directly. Different labs conduct different typs of soil tests. Look for one that tests for contaminates as well as basic soil quality/nutrient content.

Here is a link that might be useful: Analytical soil labs - pdf

RE: Soil testsing in Seattle

I got this response from WSU. maybe it's something they used to offer?

-----Original Message-----
From: Myhre, Liz []
Sent: Wednesday, March 04, 2009 9:29 AM
To: Cheryl Conklin
Subject: RE: WSU soil testing?

Hi Cheryl, we don't have soil testing at WSU. However, if you go to our webpage: there's a list of Pacific Northwest soil test labs that you can send samples to, as well as information about how to collect samples, how to interpret the results, and a few other soil testing publications.

Liz Myhre
Washington State University
Puyallup Research Station
NOTE new street address as of 1 March 2009:
2606 W Pioneer
Puyallup, WA 98371 (253) 445-4558

From: Cheryl Conklin []
Sent: Wednesday, March 04, 2009 9:24 AM
To: Myhre, Liz
Subject: WSU soil testing?

I've searched to no avail on the WSU Extension site to get information about its soil testing service. Could you help me?

RE: Soil testsing in Seattle

It is exactly the same link as the one I posted and the one bboy referred to. Pull up the link emailed to you by WSU, scroll down to the section on "soil test laboratories" and click on the first listing where it says 'online pdf'. You have to have Adobe installed to read pdf files.

RE: Soil testing in Seattle

Yep, garden gal, but in the link, WSU isn't listed as offering a soil test. For WSU, it states that they "Focus on plant problem diagnosis and insect identification".

This might have been something that was offered in the past, but, per the link and the above e-mail from the WSU employee, soil tests don't appear to be offered anymore by WSU...... That could explain why Seattle Tilth directs people to KCD and to Mass. for getting soil tests...

RE: Soil testsing in Seattle

For contaminants, you could try Analytical Resources Inc. in Tukwila --

For "petroleum residues" you'll probably want to test for TPH-Dx (diesel range hydrocarbons) and/or TPH-Gx (gasoline range hydrocarbons). I think each test is about $80, or so. Tell them more specifically what you are worried about and they'll recommend the most appropriate test.

I'm not sure if ARI does fertility tests. Many folks around here send their samples to the University of Massachusetts for fertility testing. --

RE: Soil testsing in Seattle

WSU has not directly provided soil testing services for years (as is the case with most of the other west coast land grant universities/extenstion services). Insufficient facilities and staffing for the volume. That's why they offer such a comprehensive listing of soil testing labs.

For basic soil testing (nutrient content, pH, organic matter, etc.) I'd recommend Soil and Plant Lab in Bellevue. For more extensive testing for heavy metals or contaminates/pathogens, I'd recommend SoilTest Labs in Moses Lake. Call and ask which of their many services would be most appropriate for your situation.

Here is a link that might be useful: SoilTest Labs

RE: Soil testsing in Seattle

I just started a new organic garden this year from tilling up my grassy backyard! I bought a soil tester, so what are good levels to start a vegetable garden? By the end of the summer I will have plenty to compost into the garden but I am not sure how to measure what is good start off with as far as nutrient levels, thanks for your assistance--
Sweet pea/Auburn

RE: Soil testsing in Seattle

Home test kits to determine nutrient levels tend to be woefully inaccurate. It would be better to have at least a baseline professional lab test done to begin with. One of the several testing labs listed above can do that for you. If you access their websites and/or call them, they will tell you how to go about preparing the soil sample and the costs for the test. Provided with the test results will be the basic recommendations for amending your soil to provide the best nutrient levels.

With the home test kits it's pretty much a guess and by golly situation :-) However, adding 4-6 inches of a good quality compost to the planting area should get you started in the right direction. But I'd bite the bullet and get a professional test.

RE: Soil testsing in Seattle

UW's Elisabeth C Miller library recommended the U Mass's AMherst campus when I asked them this question about a year ago. The message is below. They are reasonably inexpensive and the turnaround time was around 1 week, iirc. They can both email and post the results back to you.

The lab did testing on PH, basic PNK and lead levels, and can also test for contaminants for a fee. They have recommendations based on the intended usage profile of the area (lawn, fruit trees).

----- BEGIN PASTE -----------
Here are links to information and resources for soil testing. The UMass
Amherst facility is easy to use, and well-suited to home gardeners (as
opposed to agricultural soil testing).

RE: Soil testing in Seattle

  • Posted by corrine1 7b Pacific Northwest (My Page) on
    Tue, Jan 24, 12 at 13:07

Who has used what soil testing service & how it helped or not for an established garden with yearly additions of organic matter, fertilizer, & limes?
Is it really useful or is the clear jar test enough as explained after the 2 soil test resources? Testing is only as useful as the interpretation & application to the garden setting. I'm not a soil scientist, so would appreciate the simple answers, please. :o) What has worked for your garden in western WA?

Two cheap sources as compared to Peaceful Valley $50 test.

1. $8 from U of Connecticut

2. $10 from U of MASS

Includes pH, Buffer pH, Extractable Nutrients (P, K, Ca, Mg, Fe, Mn, Zn, Cu, B), Extractable Heavy Metals (Pb, Cd, Ni, Cr), and Extractable Aluminum, Cation Exchange Capacity, Percent Base Saturation.

1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. For example, a good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains� too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer your soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.

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