Brad Withrow-Robinson, Forestry & Natural Resources Extension, Benton, Linn and Polk Counties. Photos Jody Einerson, Benton County Extension.

Backpack sprayers are often used to apply herbicides to control weeds in forestry and conservation work.   It is often helpful to apply two or more chemicals at a time in a “tank mix”.  For example, it is common to apply a foliar herbicide to kill actively growing weeds, along with a soil active herbicide to prevent new weeds from emerging over the following growing season.  Or it may be useful to apply two different herbicides with similar action, but that target different types of weeds (grasses v broadleaf plants).  Be sure to review the post on calibrating a backpack sprayer.

Continue reading

Brad Withrow-Robinson, Forestry & Natural Resources Extension, Benton, Linn and Polk Counties. Photos by Jody Einerson, Benton County Extension.

In many of our herbicide application situations, the objective is to treat an area, such as a plantation of young trees, at a specific application rate.  By rate, we mean applying a specific amount of a material over a given area (e.g. ounces of product per treated acre).  This is essential when applying soil active herbicides, and also for area treatments (as opposed to targeted spot treatments) with foliar herbicides, particularly if the spray mix will be contacting the seedlings, such as in “over the top” applications. Applying too little material will not give you effective weed control, wasting time and money.  Too much material risks killing seedlings and other desirable plants, or causing other environmental damage.  Figuring out how much spray you are applying so that you can calculate how much herbicide to mix into the spray tank is called calibration.

Once you have calibrated your backpack sprayer, you can apply spray in any number of patterns, and still be putting out an accurate amount of material on a per acre basis.  That means you can accurately treat the entire plantation (broadcast), or discreet parts of that plantation such as row strips or patches around trees with confidence. 

Calibration requires a few simple activities and calculations, in two steps.  Here is a simplified refresher:

Step 1: Find the Application Rate (Gallons/Acre, gpa) you apply

Continue reading

Brad Withrow-Robinson, Extension & Natural Resources Extension agent for Benton, Linn and Polk Counties.

Spring is the key time to tackle many non-woody weeds.  These non-woody (also called “herbaceous”) plants  include grasses and many common flowering plants including clovers, thistles, oxeye daisy, tansy ragwort and groundsel.  There are many native and also non-native herbaceous plants in the fields and forests of Oregon.

Taking care of unwanted plants/weeds in often an important part of taking care of your land.  Herbaceous weed control if often part of these common objectives:

  • Successfully planting tree and shrub seedlings
  • Reducing fine fuels defending against wildfire
  • Enhancing forest diversity/improving wildlife habitat
  • Easy access and enjoyment of your property
Continue reading

UPDATE (May 6)

Due to COVID , Amy’s family has Postponed the Celebration of her life event that was scheduled for June 2020.  We will continue to update information about this and other activities at the bottom of this blog post.

As many readers in the north Valley are aware, our friend and colleague Amy Grotta passed away in late December in Portland.  Amy had been living with cancer for a number of years and her fighting spirit had been an inspiration for all of us.  She was an incredible human being, deeply respected and loved by all who knew her.  We will carry her memory with us always.

Amy was the OSU Forestry & Natural Resources (FNR) Extension agent in Columbia, Washington and Yamhill Counties.  I had the pleasure and good fortune of working with Amy for ten years since she joined FNR Extension.  Since we worked in adjacent Counties with many similarities in climate, forest types, and audiences, I guess it was natural for us to collaborate on projects.  We shared writing for the Tree Topics Blog and our individual newsletters, designed and taught many classes and events together. She was very talented and such a pleasure to work with.  Amy was an inspiration to me.

Continue reading

Brad Withrow-Robinson, Forestry & Natural Resources Extension agent, Benton, Linn and Polk Counties, and Amy Grotta, OSU Forestry & Natural Resources Extension agent, Columbia, Washington and Yamhill Counties.

MWM Class of 2019

We are excited about recently finishing a Master Woodland Manager (MWM) training and welcoming a new group of MWM volunteers in the mid and north Willamette Valley. The 22 local landowners hail from Benton, Polk, Washington and Yamhill Counties, and bring a wide range of interests, experience and skills to the program.  This advanced training included eight full days of classes and field tours, over four months, providing participants with lots of practical information and opportunities to share and learn from classmates.

Continue reading

Brad Withrow-Robinson, OSU Forestry & Natural Resources Extension agent for Benton, Linn and Polk counties.

A recent clearcut/new plantation/rebounding forest in Coast Range foothills

Forests disturbed by fire or harvest look different than they did before the disturbance.  Just how different depends on the size and intensity of the disturbance, of course.  It’s no surprise that a site changed by fire or harvest clearly loses its value to certain wildlife species who like dark, closed forests.  But, disturbance creates opportunities for many other species of plants and animals which prosper in the different, more open environment as the forest rebounds. 

Continue reading

Brad Withrow-Robinson, OSU Forestry & Natural Resources Extension agent for Benton, Linn and Polk counties.

Mature forest in western Oregon

People enjoy and cherish Oregon’s forests for a number of reasons.  High among them are the beauty and the variety of plants and animals that live there.

While most of us picture older forests when we read that, we would be wrong to think of that as the complete picture.  Nonetheless a large part of our emotional, scientific and social energy is directed towards those older forests.

Continue reading

Brad Withrow-Robinson, Forestry & Natural Resources Extension Agent, Benton, Linn and Polk Counties. 

 

We have written about forest diversity, its importance in providing habitat for different species, or a species at different seasons or at different stages of its development.  We have addressed the forest, trees and shrubs in particular, but the importance of habitat diversity applies to other parts of the forest environment too.  Like streams.

Guillermo Giannico discusses aquatic habitats along Griffith Creek, Benton Count.

We learned about the importance of having different stream habitats to support fish, insects and other aquatic life while on a recent Extension tour.    A stream can have many types of habitat.  The anatomy of a stream (the stream’s morphology) can be described in terms that are familiar to anglers: pools, riffles, glides, bars and tail outs.  Each term describes a different combination of water depth and flow that together provide a type of habitat.  You can see and often hear this:  Some parts are quiet (pool and glide), some gurgle their presence to those nearby (a riffle), while falls and a plunge pools announce themselves at a distance.  Aquatic biologists get excited about streams with a good mix of these habitats in a stream reach, just as wildlife biologists get excited by forest structure and snags.  Hmm.  Continue reading

Brad Withrow-Robinson, Forestry & Natural Resources Extension Agent, Benton, Linn and Polk Counties. 

I was recently on a tour where we looked at how growing conditions, productivity and plant communities all change across the landscape according to elevation, soils, rainfall, aspect and other factors.  These are often included in the term “site productivity”.  These factors give important insights to the ability of a site to support different types of plants, and also how well they will grow there.  This capacity to produce biomass, or support tree growth is often expressed in the important forestry concept of site class as described in this article.

There is something odd about this rock….

We traveled from near the crest of the Coast Range back to the Valley floor to watch changes in site class and vegetation.  Our final stop was a rock sitting on a small hill beside a vineyard in Yamhill County, looking out across the Willamette Valley.

It is a large rock (about 90 tons), unrelated to any of the bedrock of the hill.  This rock helps tell a story of events during the last ice age that shaped the Willamette valley and its historic vegetation.  It influences the present, largely agricultural, vegetation as well. Continue reading

Brad Withrow-Robinson, Forestry & Natural Resources Extension agent for Benton, Linn and Polk Counties.

The woods are full of living things, all contributing to the forest’s diversity: Trees; check. Shrubs; check. Woodland flowers; check. Birds; check. Obvious enough, right?
But there are all sorts of less-obvious things which are seen only occasionally, such as mushrooms (fungus), many often-tiny things like insects, or secretive things such as amphibians. All add to the diversity, and many play important roles in how a forest functions
Let’s take a look at some more obscure but fascinating members of the forest community: lichens. We’ve all seen them. They are everywhere, including your woods. But what is a lichen? Continue reading