Do I need to Spray before planting?

Spraying Scotch broom along the road.

The official term is “Site Preparation Spray” and the answer again is: it depends on where your property is located and how soon after harvest you will be planting.

Site Preparation Spraying means treating the vegetation with chemicals to kill the weeds and allow the seedlings you will be planting to get a head start. Site Preparation spraying can be done with a helicopter, but almost all small landowners use backpack sprayers. Spraying should be done in the summer when the plants are growing.

Most timber companies will harvest the trees, then spray the following summer, and then plant the following spring. If the harvest happens during the summer, some companies will wait a full year to spray. A typical schedule would be harvest timber in Summer of 2021, Spray Summer of 2022 and plant the spring of 2023.

Spraying the weeds eliminates any vegetation that can and will compete with the seedlings you will be planting. In some areas, like Mason and Kitsap counties where are tree farms are located, spraying is almost a necessity. We have found the money spent on spraying is a worthwhile investment in the survival of the seedlings. In areas where scotch broom is found, you may need to spray multiple times to give the seedlings a chance to grow above the weeds.

In areas of good soil, for example in Lewis County, you can get away with harvesting the timber in the summer and planting the following spring. The trees can grow very fast in this type of soil and the seedlings should outgrow the competing vegetation.

Spraying will cost additional money from your timber harvest profits. Spraying cost will vary, but you should expect to pay a minimum of $2000 and up to $200 an acre depending on types and amounts of herbicides used. We spent over $4000 for a crew of six guys to treat 25 acres of bare land with several chemicals.

In general, spraying is worth the extra cost in most areas. Spraying makes sense if you will be holding your property long term and you would like the most timber value and health from your land in the future.

What about the animals in the area? Won’t they be affected by the spray? We have a large number of deer that live on our tree farms. We have noticed tracks where deer have continued to use our land before and after spraying. We have found virtually no change in animal behavior before or after spraying on our tree farm.