Wild Blueberry Management Updates_ June 12, 2024

Wednesday, June 12, 2024

 

 

Hello, everyone

 

In this quick mid-week update, we show some highlights from a recent wild blueberry growers meeting.

-       Kentville Degree Day Accumulations

-       NS Wild Blueberry Weather Stations GDD Accumulations

-       Spreading Dogbane Management in Wild Blueberry Fields

 

Kentville Degree Day Accumulations

 

Figure 1: Heating degree day accumulations for plant (above 5°C) and insect (above 10°C) development from March 1 to June 9 for the past 17 seasons. Provided by Jeff Franklin (AAFC Plant Physiology).

 

As of June 9, this year’s GDD accumulation trend in NS is still ahead of the provincial 5- and 10-year averages. Table 1 shows the difference between the 2024 and 5-year average is about 50 (433.3-385). At this time of the year, we gain about 12 GDD daily across the province. That’s about 4.2 days earlier than our normal management schedule.


Table 1. Degree day accumulations as of June 9, 2024. All data are taken from the Environment and Climate Change Canada weather station located at the Kentville Research and Development Centre. Calculations are based on a start date of March 1 and calculated using the single-sine method.



Wild Blueberry GDD Updates_ April 1- June 10


Figure 2. GDD Summary, April 1- June 10

 

Spreading Dogbane Management in Wild Blueberry Fields

Figure 3. Spreading Dogbane with flowers and leaves

 

Spreading Dogbane (Apocynum androsaemifolium L.) is a perennial plant and a troublesome weed in wild blueberry fields. In a 2017-2019 weed survey, this weed appeared in about 20% of the total wild blueberry fields in NS. Over the last few years, we have been noticing that this weed is spreading very fast and the occurrence of this plant in blueberry fields is increasing. The primary spreading method of dogbane is via horizontally growing roots which helps to form ever-expanding patches of dense shoots (Figure 4).

Figure 4. Dense Spreading Dogbane Patch in an infested wild blueberry field

 

Cutting, mowing, round up applications, and using Dicamba products (Banvel and Engenia) are all common from past conversations with growers. They have their own pros and cons. I only discuss further the industry-standard and research-based recommended management practices.

Growers can access Banvel and Engenia at the moment. Dicamba products will hurt wild blueberry plants so we only recommend spot spray the recommended products in wild blueberry fields. The initial application is recommended when dogbane patches are in the early bud stage (Figure 5). Further applications might be needed. A sticker/adjuvant is recommended to improve product efficacy and control results. Please read the product label. The below information is just some quick numbers (Figure 6) to help you to cross-check. Please also go through sections in the label including mixing instructions and spraying instructions to avoid any factors that might affect product efficacy.


Figure 5. Spreading Dogbane in Early Bud Stage

 

Figure 6. Recommended Product Rates for Spreading Dogbane Management

 

 

Have a great week!

Hugh