Hedera crebrescens M.Bényei-Himmer & M.Höhn

Juvenile Leaf Shape

On the creeping shoots of Hedera crebrescens, juvenile leaves are three-lobed. The upper, central lobe is dome-shaped and sharply pointed.

Leaf Size and Base

Leaf bases often overlap, and leaf blades are broad, measuring nearly as wide as they are long.

Frost Tolerance

This ivy is slightly sensitive to frost, and suffers damage after long periods exposed to temperatures below −10 °C (14 °F).

Umbel Fertility

Only the terminal umbel produces fruit; all lateral umbels abort and wither.

Berry Characteristics

The berries within the terminal umbel are densely packed, green when immature and turning black once they ripen.

Species Distribution

Hedera crebrescens was first identified in Hungary, and has also been found in Austria, Germany, the Netherlands, Slovakia, and Ukraine.

Habitat Preference

It prefers shaded, semi-humid conditions, and most commonly grows along railways, in and around cemeteries, parks, and unmaintained gardens.

Invasive Spread

Observations recorded since the late 2010s show that H. crebrescens spreads easily, and is displacing other native ivy species from their habitats in parts of central Europe.

Research Needs

Further studies are needed to assess the species' growth and distribution, and to put in place measures to control its spread.

Citizen Science Mapping

In 2022, the citizen science Ivy Mapping Project was launched in Hungary, which aims to map the current distribution of H. crebrescens using volunteer work.