Nectria rubifaciens: The Tiny Fungus That’s Not So Friendly to Your Berry Patch
If you’ve ever noticed small, bright orange or reddish bumps dotting the canes of your raspberry or blackberry plants, you may have encountered Nectria rubifaciens. Don’t let the fancy Latin name fool you – this isn’t a plant you’d want to add to your garden wishlist. Instead, it’s a fungal pathogen that’s native to North America and has a particular appetite for our beloved berry bushes.
What Exactly Is Nectria rubifaciens?
Nectria rubifaciens is a parasitic fungus that belongs to the group of organisms we call plant pathogens. Unlike the plants we typically celebrate in native gardening, this little guy makes its living by causing problems for other plants – specifically by creating cankers (those unsightly, sunken areas of dead tissue) on woody stems and canes.
The fungus produces tiny, flask-shaped fruiting bodies called perithecia that appear as bright orange to reddish bumps on infected plant material. These colorful dots might look almost decorative at first glance, but they’re actually the fungus’s way of reproducing and spreading to new host plants.
Where You’ll Find It
This fungus is found throughout North America, wherever its favorite host plants grow. It’s particularly common in areas with raspberry and blackberry cultivation, both in wild settings and cultivated gardens. The fungus thrives in the same climates that support healthy berry production, which unfortunately means it’s often right where we don’t want it.
Is It Beneficial to Your Garden?
In short, no – Nectria rubifaciens is not a welcome guest in most gardens. Here’s why:
- Plant damage: It causes cankers that can weaken or kill berry canes
- Reduced fruit production: Infected plants often produce fewer berries
- Spread potential: The fungus can spread to healthy plants through wounds or natural openings
- Aesthetic issues: Creates unsightly bumps and dead areas on plant stems
However, like all organisms in nature, it does play a role in the ecosystem by helping to decompose dead and dying plant material. It’s just that most gardeners would prefer this decomposition happen elsewhere!
How to Identify Nectria rubifaciens
Spotting this fungus is relatively straightforward once you know what to look for:
- Location: Look on the canes and stems of raspberry, blackberry, and related plants
- Appearance: Small, round, bright orange to red bumps (about 1-2mm across)
- Texture: The fruiting bodies have a slightly raised, dome-like appearance
- Pattern: Often appears in clusters or lines along infected canes
- Associated damage: You may also notice cankers, dead patches, or overall decline in affected canes
Managing This Uninvited Guest
If you discover Nectria rubifaciens in your garden, don’t panic. Here are some practical steps to manage it:
- Remove infected material: Prune out and dispose of affected canes, ideally during dry weather
- Improve air circulation: Ensure good spacing between plants to reduce humidity
- Practice good sanitation: Clean pruning tools between cuts and dispose of infected material in the trash (not compost)
- Choose resistant varieties: Some berry cultivars show better resistance to fungal diseases
- Avoid wounding: Be gentle during cultivation to minimize entry points for the fungus
While Nectria rubifaciens might not be the kind of native species we celebrate in our gardens, understanding what it is and how to identify it can help you maintain healthier berry plants. Sometimes being a successful native gardener means knowing not just what to grow, but also what might be working against your gardening goals!
