Phoradendron

About 235-240 species; see text Phoradendron is a genus of mistletoe, native to warm temperate and tropical regions of the Americas.

The foliage is dichotomously branching, with opposite pairs of leaves; these are fairly large, 2–5 cm (0.79–1.97 in) long, green and photosynthetic in some species (e.g. P. leucarpum), but minimal in some others (e.g. P. californicum).

The fruit is a berry, white, yellow, orange, or red when mature, containing one to several seeds embedded in very sticky juice, called viscin.

Leafy mistletoes seldom kill but they cause stress reducing crop productions in fruits and nut trees.

[7] Phoradendron plants can be distinguished from mistletoes in other genera in Viscaceae by their inflorescences, which lack leaves and come from a single branching point or apical meristem.

[8] Phoradendron presents serious problems along rivers, streams, parks, and golf courses with large cottonwood trees.

[10] Other common symptoms include swelling formations of witch's broom, dieback, and weakened branches.

[11] Phoradendron species are hemiparasites which produce their own chlorophyll but rely on the host plant to provide water, minerals, and other nutrients.

The haustorium is a root-like structure that penetrates the host plant's bark and cambium, reaching the xylem and phloem where it extracts water and minerals, primarily carbon and nitrogen compounds.

[14] The most important birds for effective dispersal include the cedar waxwing, euphonias, silky-flycatchers, bluebirds, and thrushes.

[15] Control and management regimes include watering the host plant to improve its vigor, and removing infested vegetation.

The mistletoe berries may attract frugivorous birds (e.g. thrushes) to eat the host juniper's seeds and disperse them.

Phoradendron strongyloclados showing leathery leaves and an inflorescence resulting from one apical meristem.
Multiple Phoradendron individuals parasitizing an oak tree. While lower branches show new leaf growth, the mistletoe appears to be negatively affecting the tree's budding in the upper branches.
Phoradendron californicum (Desert Mistletoe), Granite Mountains, Mojave Desert , California
Phoradendron sp. on Spanish oak