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Effects of mistletoe (Phoradendron villosum) on California oaks.

ABSTRACT: Mistletoes are a widespread group of plants often considered to be hemiparasitic, having detrimental effects on growth and survival of their hosts. We studied the effects of the Pacific mistletoe, Phoradendron villosum, a member of a largely autotrophic genus, on three species of deciduous California oaks. We found no effects of mistletoe presence on radial growth or survivorship and detected a significant positive relationship between mistletoe and acorn production. This latter result is potentially explained by the tendency of P. villosum to be present on larger trees growing in nitrogen-rich soils or, alternatively, by a preference for healthy, acorn-producing trees by birds that potentially disperse mistletoe. Our results indicate that the negative consequences of Phoradendron presence on their hosts are negligible-this species resembles an epiphyte more than a parasite-and outweighed by the important ecosystem services mistletoe provides.

SUBMITTER: Koenig WD

PROVIDER: S-EPMC6030594 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Effects of mistletoe (<i>Phoradendron villosum</i>) on California oaks.

Koenig Walter D WD Knops Johannes M H JMH Carmen William J WJ Pesendorfer Mario B MB Dickinson Janis L JL

Biology letters 20180601 6

Mistletoes are a widespread group of plants often considered to be hemiparasitic, having detrimental effects on growth and survival of their hosts. We studied the effects of the Pacific mistletoe, <i>Phoradendron villosum</i>, a member of a largely autotrophic genus, on three species of deciduous California oaks. We found no effects of mistletoe presence on radial growth or survivorship and detected a significant positive relationship between mistletoe and acorn production. This latter result is ...[more]

PMID: 29925562

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