High copper level in soil

Asked November 21, 2019, 10:29 PM EST

In our back yard, we have lost 3 trees in one spot. Two Siberian Cypress and one Norway Spruce. When we lost the second one, we got a detailed soil test in October 2018, which revealed a high level of copper (.22 ppm). We were concerned it was coming from our lawn service's fertilizer, so we discontinued service (last service in fall 2018). We just planted another Norway Spruce and want to know if there is anything that can be done to neutralize the copper level, as we are at a loss for what is killing these trees and don't want to lose another. There is an abandoned buried electric fence line nearby that could have breaks in it. Would that emit copper throughout the soil? In March 2019 we took samples from our backyard and our front yard to see if the level was high in the front yard, also and the values were 0.16 and 0.14 ppm, so that makes us think it is probably not the broken fence line. The copper level history is as follows: 10/30/2018 0.22, 12/11/2018 0.32, 03/09/2019 0.16 & 0.14, 06/29/2019 0.09, 10/30/2019 0.20. We tested our neighbor's soil, who doesn't get any lawn service, in their back yard (approximately 125 feet from the tree) on 03/24/2019 and their level was 0.06. We can provide the detailed soil analysis reports to see if there's something else you all see that may be the cause. I would also like to note that we have approximately 25 trees and shrubs planted in our back yard and aside from one Colorado Spruce (which had a disease in the area run through), this is the only tree/spot that we have had problems with.

Washington County Maryland

1 Response

Your copper levels are extremely low and are not causing the problem. Typical background levels in rural areas is 2-20 ppm. You would not see copper toxicity unless soil levels were well over 50 ppm.

You did not mention the symptoms of the trees (branch dieback, etc.) and how old they were. Once trees are dead it is difficult to determine why.
There could be several reasons for decline. When plants are subject to poor drainage, poor soils, drought, poor planting techniques (planting too deeply, excessive mulch, etc.) they can be susceptible to disease and insects issues. Here is our site and publication on these types of abiotic (cultural and environmental) problems. They can be difficult to diagnose.
https://extension.umd.edu/hgic/topics/cultural-and-environmental-0
https://extension.umd.edu/sites/extension.umd.edu/files/_docs/programs/hgic/HGIC_Pubs/TreesandShrubs...

Also, many woody plants have declined due to the abnormal rainfall that we
received last season and this spring. Saturated soils have reduced oxygen and this affects the roots. The drought that we had this summer affects the root system too.

You mentioned that you recently planted a Norway spruce. The pH range of spruce is about 5-6. This tree has a shallow spreading root system and grows well in a moderately moist, sandy, acid and well drained soil. It can be planted in average soils provided adequate moisture is provided in the early years of establishment.

Check the drainage in the area and make sure the soil drains well.
Also, make sure the tree is not planted too deeply. You should be able to see the flare of the trunk where it joins the root system. Mulch should be no thicker than several inches and keep away from the base of the trunk. Keep the tree watered up until the ground freezes. Monitor the soil moisture the next several growing seasons and water during dry periods. Take a look at our website for the planting process and post planting care. https://extension.umd.edu/hgic/topics/planting-process

Please send us photos of the plants as soon as you notice symptoms so we can see what you may be dealing with.

Marian









to monitor the soil mois;ture during dry periods and water if need be the next several growing seasons.