OREGON STATE UNIVERSITY

Oberteuffer Forest Experiments

In the northwest corner of the Oberteuffer Forest, two experiments are testing ponderosa pine, Douglas-fir, and western larch seedlings. The goal of these experiments is to show how various types of seedling stock types, weed crontrol, and animal damage protection affect the growth and survival of seedlings. Cost and comparisons are available.

First Experiment

The pictures below show trials of different site preparation treatments and the bar graph summarizes seven years of results for ponderosa pine.

Ponderosa pine reforestation demonstration showing all treatments five years after planting.
Ponderosa pine reforestation demonstration showing all treatments five years after planting.

Typcial growth of 5-year old ponderosa pine 1-1 seedlings after treatment with Velpar herbicide.
Typcial growth of 5-year old ponderosa pine 1-1 seedlings after treatment with Velpar herbicide.

2-0 ponderosa pine seedlings five years after a spot treatment with Velpar herbicide.
2-0 ponderosa pine seedlings five years after a spot treatment with Velpar herbicide.

Second Experiment

A similar study has been initiated with western larch and Douglas-fir. The picture below shows the positive effects of using a spot application of Oust herbicide to control competing vegetation around western larch.