Measuring conifer trees at first thinning

Teagasc Forestry Development Department in association with the Forestry Division, DAFM invites forest owners to a practical timber measurement course on Wednesday, March 15, in Stradone at 10am focusing on conifer forests at first thinning stage.

Thinning is the practice of removing a quantity of trees (standing volume) at intervals over a number of years in the forest. The emphasis is to concentrate the growth on individual trees to produce quality grade sawlog. At about year 15 the forest should be assessed to see is it ready for thinning. Measurements taken at this time will not only determine the age of first thinning, but also the interval in years between 2nd and subsequent thinnings and the approximate age of clearfell.

First thinning is a necessary forestry operation, it is a means to an end. It is a management tool aimed at improving the value of the crop in the long run. It may not necessarily be a money making exercise; if associated costs like foresters fees, entrance and forest road construction are met, with some money coming back to the owner, then it is a job well done. The infra-structure will be in place for second and subsequent thinnings and the size of the trees to be removed are bigger so the returns to the owner greater.

Owners who have completed a first thinning may think they have their work done and that the forest will more or less take care of itself from here on in. The first thinning in general is a straight forward line and selection thinning i.e. remove one line in seven and selecting the smaller trees in between. This course is aimed at forest owners who have conifer forests at first thinning stage. Teagasc forestry advisers will discuss and demonstrate a range of important measuring techniques. There will be practical tree marking exercises with all participants given time and opportunity to practice and consolidate what they have been shown. The courses will include:

o Finding out if the forest is ready for thinning;

o Determining the productivity of the forest;

o Estimating the volume to be removed;

o Determining what trees should be removed as thinnings

o Estimating the % pulp, stake and palletwood assortments;

o Examining other factors that may affect the thinning intervention;

All courses are free, but pre-registration is necessary, as each will be limited to 20 participants. Early booking is advisable. See: www.teagasc.ie to secure your place on the course.