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Monday - March 21, 2011

From: Lathrop, MO
Region: Midwest
Topic: Compost and Mulch, Planting, Soils, Trees
Title: Native plants for clay soil in Lathrop MO
Answered by: Barbara Medford


My family just moved to the north Kansas City, MO area and would like to know what native species, both perennial and tree, will do best in the clay soil. It has already proven problematic as we have managed to make large mistakes. We planted a row of Eastern White pines that died; most likely all from root rot. After talking to a neighbor, he informed us that we should next time place the tree on a rock/improved soil bed..then plant with several inches of the root ball ABOVE ground (incorporating both improved and local soil to fill and cover). I just don't want any further decisions/purchases to go wrong. Thanks in advance for any help you can send my way.


You have been suffering from what we call the "leap before you look" syndrome, in which you spend a lot of time and resources planting plants that are very likely doomed from the start. Just because you can buy something locally doesn't mean it will survive locally. Allow us to introduce you to our Native Plant Database and all the ways you can get information on plants native to your area and get back to "look before you leap."

To start on learning how to use our database, we will use the tree that died, Pinus strobus (Eastern white pine) as an example. Follow the plant link to our webpage to learn more about that plant. Read the whole page, but especially note the Growing Conditions:

Water Use: Medium
Light Requirement: Sun , Part Shade , Shade
Soil Moisture: Moist , Dry
Soil pH: Acidic (pH<6.8)
CaCO3 Tolerance: None
Soil Description: Fertile, moist, well-drained soils.

There are two clues in those Conditions that we regard as crucial in your case. First, the tree likes an acidic soil. We don't know what acidity your soils have, but areas in which leaves (and pine needles) have fallen from native forests for generations usually have a somewhat acidic soil as a result of the decomposition of those leaves on a forest floor. The other point you need to consider if you have a clay soil is the comment on "Fertile, moist, well-drained soils." A clay soil is made up of very tiny particles, which swell as they absorb water, and become almost impervious to oxygen. Clay soils often are quite fertile, but the nature of the soil prevents the access by tiny rootlets of necessary nutrients in the soil. Worse, the roots can end up actually standing in water because the clay will not allow the moisture it has absorbed to drain away. This could be a clue to the root rot possibility you mentioned.

The last factor that should have been checked in advance was whether or not that plant already grows in your area, which would indicate whether or not your area had hospitable conditions for it. We went to the USDA Plant Profile map for Pinus strobus and discovered that is found only in 6 counties in southeastern Missouri, while Clinton Co. is in northwestern Missouri.

Now that you have seen what kind of information you can get from our plant pages, we will walk you through making your own searches for trees native to your area. Using the same method, you can search for shrubs, herbaceous blooming plants, vines, succulents and ferns, selecting plants that have the Light Requirements and Soil Moisture you have available, as well as soil types those plants prefer. Begin by going to our Recommended Species, click on Missouri on the map, which will give you a list of 157 plants native to Missouri and are commercially available; to narrow the list down, use the sidebar on the righthand side of the page, indicating "tree" under General Appearance, as well as the other conditions where you will be planting, such as Light Requirements and Soil Moisture, then click on "Narrow Your Search." 

We went through the resulting list and chose those that tolerated clay soils. To be even more sure these were good tree choices for you, we went clear down the plant page to "Additional Resources" and clicked on the scientific name for each plant on the USDA line. This will give you a map of North America with the states where that plant grows in green. Click on the state (Missouri) and you will get a map of that state with the counties where that plant grows. We have selected only those plants that grow in northwestern Missouri. Also, virtually every one of these trees were said to need "deep, moist, well-draining soils," which, as you heard above, are not easy to come by in clay, but amendments and special preparations can be made. We find this article from TreeHelp.com How to Plant a Tree very useful; we would only suggest that you use compost instead of peat moss-this will help with both the plant nutrition and with the needed drainage.

Trees for Northeastern Missouri in Clay Soil:

Aesculus glabra (Ohio buckeye)

Cercis canadensis (Eastern redbud)

Crataegus crus-galli (Cockspur hawthorn)

Ostrya virginiana (Eastern hop-hornbeam)

Malus ioensis (Prairie crabapple)

Platanus occidentalis (American sycamore)

Quercus macrocarpa (Bur oak)

Tilia americana (American basswood)

From our Native Plant Image Gallery:

Aesculus glabra

Cercis canadensis

Crataegus crus-galli

Ostrya virginiana

Malus ioensis

Platanus occidentalis

Quercus macrocarpa

Tilia americana








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