Silvicultural considerations in established alder stands Jeff DeBell Washington DNR June 10, 2009

Topics Background Thinning in alder stands Pruning in alder stands Differences between natural alder stands and plantations

Alder Height Growth

Uniform early spacing is critical Alder leans toward openings in the stand Keep even spacing to keep stems straight

Thinning – growing the crown

Crowns expand by getting taller as well as wider after thinning

When should you thin? Age 5-10 years Before crown ratio drops below 30% Early gives best diameter; later gives best crown recession Ideal at about age 6-7 –50% crown ratio –25-30 feet tall –Live crown starts about 15’ from ground

To what spacing should you thin? Ideally, set spacing based on a relative density measure For a simple approach, thin to a 13’ spacing

Pruning alder

Pruning: lessons from research Time of year is not important Small branches heal over more quickly than large ones Decay not an issue Epicormic branches not an issue In young vigorous plantations, clear wood production begins in 2-3 years

How to prune Can start as early as age 3 Any time of year Wait one growing season if thinned Remove no more than 1/3 of live crown Leave at least 50% live crown ratio

Natural vs. Planted Stands

Advantages of planted stands Moderate density = good growth Even spacing = good form Volume concentrated in fewer, larger trees Reach target diameter sooner Higher total volume??

For more reading: Can order hard copy from USFS PNW Research Station Ask for PNW-GTR-669 Can download PDF at URL below

Streaming video presentations from “Red Alder: A State of Knowledge” Available at University of Washington’s Rural Technology Initiative Website Includes 45 presentations Can order a DVD with all presentations for $10 Watch on your computer at _symposium/index.asp