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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

Irrigating Pastures

As summer approaches and the soil dries, forage plants become dormant. Some years in drier areas of Oregon dormancy may begin in the late spring. If you have irrigation rights, your pastures can provide supplemental nutrition even during the dry summer months. Although this article targets irrigated pastures, many of the principles apply to other crops. There are a number of ...

Mylen Bohle | Jul 2007 | Article

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