Holly
Botanical Name
Ilex aquifolium
Family
Aquifoliaceae (holly)
Also known as
English holly
Where is it originally from?
Europe, West Asia, North West Africa
What does it look like?
Evergreen, much-branched shrub or small tree (<12 m tall). Glossy dark green leaves (3-10 cm long) alternate along the stem, are paler below, and have wavy, thick, usually deeply serrated edges, with a spine at each point. Flowers with four white petals (3-5 mm long, Oct-Nov) occur in clusters and are followed in winter by round, bright red berries.
Are there any similar species?
Chinese holly (Ilex cornuta) has thick, glossy, almost rectangular leaves and berries in summer, the variegated form is common in cultivation. Other Ilex species are grown in cultivation but have not naturalised in NZ.
Why is it weedy?
Large, long-lived species that can withstand a variety of conditions and tolerates most soil types, but prefers good drainage, and is shade tolerant.
How does it spread?
Seed is bird-spread and it also spreads by suckering (sprouting from roots) and layering (rooting of branches that touch the ground).
What damage does it do?
Competes with native plants for light, nutrients and water. Suckering and layering allow it to form dense thickets that can dominate the tall shrub layer, creating a deep shade difficult for native species to grow in.
Which habitats is it likely to invade?
Native and plantation forest, forest edges and hedgerows.
What can I do to get rid of it?
1. Hand pull seedlings and small plants (all year round): mulch or dispose at refuse transfer station.
2. Swab stumps (all year round): cut down and paint freshly cut stumps with glyphosate (200ml/L) or a product containing 100g picloram+300g triclopyr/L (200ml/L). Dispose of cut material at refuse transfer station.
3. Bore and fill (spring-summer)): bore 1 downward angled hole every 5-10cm around the trunk, and apply 1.5 ml of a product containing 100g picloram+300g triclopyr/L (undiluted) per hole.
4. Frilling (all year round): With a sharp chisel or axe, make a deep cut into the sapwood at 5cm intervals around the base of the tree, taking care not to ring-bark the plant. Immediately saturate the cuts with 1.5 ml of a product containing 100g picloram+300g triclopyr/L (undiluted) or glyphosate (200ml/L).
What can I do to stop it coming back?
Monitor the site and treat regrowth and seedlings. If possible, search out and eliminate the source of the infestation.
