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Nitrogen-fixing trees “eat” rocks, play pivotal role in forest health

By tapping nutrients from bedrock, red alder trees play a key role in healthy forest ecosystems.

Chris Branam | Feb 25, 2019 | News Story

Predicting Nitrogen Availability from Organic Amendments: laboratory, Field, and Computer Stimulation

A study to improve the ability to predict nitrogen availability from organic soil amendments, including improved accuracy of Nitrogen availability estimates, to target amendment application rates to meet crop N needs.

Dan Sullivan, E.S. Gale, Delbert Hemphill, Craig Crogger, Andy Bary, E.A. Myhre | Apr 2018 | Publication

Nitrogen Fertilizer: Where Does it Go?

Most Christmas tree growers fertilize with nitrogen (N) intending to improve tree color, growth, and ultimately value. Where does the fertilizer go after application? How much is actually taken up by the trees, stored in the soil or lost to the environment? How much N is removed at harvest? Should growers be concerned about depletion of soil N reserves from repeated ...

Chal Landgren, Michael Bondi, Steve Webster, Rick Fletcher | Jul 1994 | Article

Estimating Nitrogen & Dry Matter From Cover Crops

Cover crops are used by many farmers, but very few know how much nitrogen (N) or dry matter they are getting from their cover crops. There are some methods in the literature for estimating cover crop contributions. We are evaluating these methods in on-farm WSARE-funded trials in the Northern Willamette Valley to find the most practical and accurate method for use on ...

Nick Andrews | Apr 2007 | Article

Are madrone trees mean?

Q: I have a small grove of Madrones behind my house. I have put a couple of annual beds under them but nothing seems to grow under them. I have looked all over the net to no avail on this issue. I did amend the soil in the beds. I also planted a few Dogwood trees under them from tiny sticks. The trees grew last summer but then the leaves started browning at the tips and curling up. I was watering the trees every two to three days during summer. What am I doing wrong?

A: View answer | View all featured questions

Native madrones are special to the Northwest

There are probably few plants that are more strongly identified with this area or are held in greater affection than the madrone tree.

Jan 27, 2006 | News Story

The ABC’s of NPK

Nitrogen Phosphorus Potassium

Lisa Ehle | Jun 2018 | Article

Use Caution When Irrigating Oaks and Madrones

Excessive summer irrigation of oak and madrone trees may promote fungal diseases such as the oak root fungus (aka armillaria root disease) and crown rot.

Jun 2018 | Article

What’s Wrong With My Madrone?

This article briefly discusses the most prevalent madrone disease problems, then offers a broader perspective on the health of this southern Oregon native.

Max Bennett, Dave Shaw | Nov 2006 | Article