Christmas Tree Grower Update - Spring 2020

The world of Christmas trees may be far from your “top of mind” concerns just now.  I get that. But eventually, life will be more normal and some of the new products and new research mentioned below will assist growers in making decisions, growing trees, and moving forward.

Below are two newly registered products that I want to alert growers about for this season. Also new, is a growth regulator product from ValentBioscience. Please note that this product is currently not registered for use. I mention it now because I anticipate registration soon and there likely will not be time to inform growers regarding pending registration prior to the time you might consider using it in late May early June.

Esplanade F (Indaziflam)

This is a Bayer herbicide that has been used in forestry for a number of years. Beginning this year, Christmas tree plantations are included on a 2 (ee) registration for Oregon and Washington. We have years of use information on Douglas-fir forest plantations, but little research information on noble, Turkish, or Nordmann firs. So, until there is more data, the label suggests using directed dormant pre-emergent applications on trees that have been field planted for one year or more. The suggested rate is 5 oz./ac. The product works by inhibiting root growth in the upper 1 inch of soil. It is very persistent and long-lived within that depth. If established plants are rooted beyond this depth, Esplanade will not be effective, so some sort of knock-down herbicide will be needed for control on established weeds. The product is only sold in 2.5-gallon containers and the approximate product cost per acre is around $36.

Transform W

This is a newly registered insecticide from Corteva. It is registered for aerial application and the “fit” in Christmas trees will likely be for aphid control. It is effective on sucking insects and moves in the xylem (water transport) so it has some systemic activity. We have been working with a similar liquid product (Closer) for the past 3 years. The new granular product should be applied at 1.5-2.25 oz./ac. From our work with the active ingredient, sulfoxaflor, it is a bit safer on beneficial insects when compared to Lorsban Advantage. The product has a DANGER, signal word on the label, but is not RESTRICTED USE. Also, Corteva just announced that it will no longer manufacture Lorsban Advantage, though other companies will continue to produce other Chlorpyrifos products,

Growth regulators for leader control

This is a project that I and others have been working on for over 25 years. Growers in Denmark and Germany have done work for even longer. The new product is S-Abscisic Acid and will be sold under the trade name ConShape. Unlike other growth regulators I’ve tested, this one stops leader growth (when used at the proper rate and time) on noble, Nordmann, and Turkish fir. I don’t want to spend time on specifics until the product is registered. If we succeed in getting registration by May, I will be developing some product use guidelines for this season. So, if this might be of interest, e-mail me around the first part of May. There is no word on product cost yet.

As I finish this article in mid-March, the COVID-19 virus continues to disrupt our lives. Social distancing and working from home are becoming the new norms. The unknowns of the next weeks or months will be challenging and confusing. My best to all of you and I’ll leave it to others for advice on the larger “picture.” Stay well. I can be easily reached by email  chal.landgren@oregonstate.edu.

Was this page helpful?

Related Content from OSU Extension

Ask an Expert

Have a Question? Ask an Expert!

Ask an Expert is a way for you to get answers from the Oregon State University Extension Service. We have experts in family and health, community development, food and agriculture, coastal issues, forestry, programs for young people, and gardening.

Ask Us a Question