Wild Blueberry
Production Guide...
in a Context of
Sustainable Development
47. Woody Plants
INTRODUCTION
The woody plants include small trees, plants and shrubs
whose stem is composed of wood (lignin) and that are used
little if at all by the forestry industry. The main species
found in blueberry fields are the following:
• willows
• birches
• serviceberries
• witherod
• sweet-fern
• lambkill
• alders
• pin cherry
• black chokecherry
• bush honeysuckle
• leatherleaf
• mountain cranberry
Infestations of these woody plants vary in magnitude,
depending on species present when the field was developed,
the vigour of the crop and the agricultural antecedents of
the field.
DESCRIPTION
Woody species are perennial, the aerial part persisting for
years. Depending on the species, reproduction may be
sexual (by seed), asexual (vegetative) or both. Vegetative
reproduction of woody plants often occurs via rhizomes
and suckers, i.e. underground stems that form roots and
aerial branches.
Figure 1. Example of woody plant in a blueberry field, trembling aspen
(Populus tremoloides Michx.)
PREVENTION
Source: Suzanne Hardy, Enracinart
Though control will not be complete, pruning by burning,
once in every two or three production cycles, reduces the dissemination of the seeds of certain species. However, it is
important to be aware that for woody plants with rhizomes, multiplication is stimulated by pruning, regardless of whether
it is done by mowing or burning.
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47. Woody Plants
CONTROL
Hand-pulling of some woody plants is possible, but not always practical given the presence of rhizomes or deep roots in
certain species.
Mowing woody plants above the blueberries can slow their development, but must be done repeatedly over the summer. It
is also recommended to remove the flowers before they can produce seed. Mowing is most effective when the field is in a
growth year, particularly since no damage will be done to blueberry flowers, buds or fruit.
Herbicides
No alternative to herbicides is currently available for controlling woody plants in blueberry fields.
Since most woody plants grow taller than the blueberry, glyphosate applied with a wick applicator is a highly feasible method
of control. This technique allows herbicide to be applied solely on the target species, without affecting any blueberry plants.
Using a manual, “hockey-stick” style of applicator, spot applications can focus on patches where an infestation threatens
to expand or otherwise reduce yield. With larger infestations, or to treat recently developed fields, a mechanized applicator
such as the Super Sponge can be used. Various brands of herbicide in which the active ingredient is glyphosate are available
on the market.
Some woody plants can be controlled by spraying a hexazinone-based herbicide such as PRONONE® or VELPAR® in the
spring of a growth year.
Two species that are difficult to eliminate are sweet-fern and bracken fern. The authors have produced separate information
leaflets for each of them (see below).
CONSERVATION OF WOODY PLANTS FOR POLLINATORS
Some woody plants provide habitat and food for native insect pollinators, particularly before and after the blooming
period of the blueberry. Wild bumblebees, which are highly effective pollinators of blueberry flowers, need flower resources
throughout the season. For this reason, it is highly beneficial to conserve or relocate certain woody plants in thickets where
they will detract little if at all from production, for example in riparian strips, around farm buildings and in windbreaks.
They can also be used in foraging patches. Among the woody species, willows and serviceberries are especially recommended
for attracting native pollinators early in the season.
COMPLEMENTARY LEAFLETS
15. Integrated Pest Management in Wild Blueberry Production
19. Pesticides Used in Wild Blueberry Production
21. Wick Applicator Calibration
27. Foraging Patches to Attract Native Pollinators
30. Managing Native Pollinators in Wild Blueberry Fields
42. Lambkill
43. Sweet-fern
45. Bracken Fern
Wild Blueberry Production Guide
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47. Woody Plants
REFERENCES
Desjardins, È.-C. and R. Néron. 2010. Guide d’identification des alliés et ennemis du bleuet nain : Insectes, maladies et végétaux.
Centre de recherche Les Buissons. 138 pp.
Duval, J. 2003. Production de bleuets biologiques. CRAAQ. 25 pp. [Online].
www.agrireseau.qc.ca/agriculturebiologique/Documents/Guide-Production-Bleuets%20Bio-CRAAQ-Janvier-2004.pdf (Page
consulted on September 15, 2010).
MAPAQ. 2004. Cahier d’autoévaluation de gestion intégrée des ennemis des cultures. Pratiques agroenvironnementales spécifiques,
bleuet nain semi-cultivé. 17 pp.
Marie-Victorin, Frère. 1995. Flore laurentienne. Troisième édition. Les Presses de l’Université de Montréal. Montréal. 1093 pp.
Yarborough, D. 2001. Cultural Management for Weeds in Wild Blueberries. Fact Sheet No. 252. The University of Maine.
Cooperative Extension. [Online].
http://umaine.edu/blueberries/factsheets/management/cultural-management-for-weeds-in-wild-blueberries/ (Page consulted on
September 15, 2010).
Yarborough, D. 2008. Organic Wild Blueberry Production. Fact Sheet No. 304. The University of Maine. Cooperative Extension.
[Online]. http://umaine.edu/blueberries/factsheets/organic/304-organic-wild-blueberry-production/ (Page consulted on
September 15, 2010).
PROJECT COORDINATION
PUBLISHING
Sophie Gagnon, Agronomist,
Coordinator, Agrinova, Alma
Project
Management
Chantale Ferland, M.Sc., Publishing Project Officer, CRAAQ,
Québec
Lyne Lauzon, Publications Coordinator, CRAAQ, Québec
ADAPTATION
Sophie Gagnon, Agronomist,
Coordinator, Agrinova, Alma
Project
TRANSLATION
Management
Rod Willmot, M.A.
REVISION
LAYOUT AND GRAPHIC DESIGN
Danielle Bernier, Agronomist-Weed Scientist, Ministère de
l’Agriculture, des Pêcheries et de l’Alimentation du Québec,
Québec
Sylvie Robitaille, Computer Graphics Technician, CRAAQ,
Québec
Gaétan Chiasson, Agronomist, Development Officer, New
Brunswick Department of Agriculture, Aquaculture and
Fisheries, Bathurst
Laurier Tremblay, Agronomist, Ministère de l’Agriculture,
des Pêcheries et de l’Alimentation du Québec, Bergeronnes
PRODUCED BY
FUNDED BY
Association
des producteurs
de bleuets de
la Côte-Nord
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Wild Blueberry Production Guide