Q: Parasitic plants

A: Repeat after me, "These are not carnivorous plants."

Many people think that, other than carnivorous plants, the rest of the plants in the botanical world lead conventional lives making food for themselves via photosynthesis. Oh, not true!

Allow me to widen your horizons. Did you know that there are parasitic plants, too? These are plants which do not make their own food, but rather live off other plants---like a tick or tapeworm might feast on an animal.

• Cuscuta japonica
• Cuscuta japonica
• Cuscuta californica
• Cuscuta brachycalyx

Creepy, huh? One example of these botanical vampires is Rafflesia arnoldii. Another is dodder (Cuscuta sp., in the Convolvulaceae family). I am particularly fond of dodder. When the seed germinates, the little seedling probes around for a host plant. When it attaches to the host, the base of the dodder dies and thereafter it gains all its sustenance by sucking juices out of the host plant. These plants do not have chlorophyll, so do not necessarily look green. Usually they are reddish, orange, yellow, or transparent. Pretty weird stuff.

If you ever see something that looks like silly string sprayed all over a plant, you are probably looking at dodder. Either that, or someone sprayed silly string on the plant.

• Nuytsia floribunda
• Castilleja rhexifolia
• Castilleja miniata
• Phoradendron flavescens

Some plants are only partial parasites. Castilleja (indian paint-brush) is such a plant. The Australian Nuytsia floribunda produces (I am so not joking!) underground shears that it uses to sever the roots of its hosts, and then greedily sucks the juices from the plant. These shears even cut through underground cables!

Mistletoe (in the Santalaceae, like Phoradendron) is the famous plant that many people use as an icon for sub-viscaceous kissing during the Christmas holiday season (very curious). But did you know that it is a partial parasite too? Sure, it has chlorophyll and so makes some food for itself, but it requires a plant host. Romantic, eh? Gimme a kiss, sweetie, we are standing underneath a parasite!

Page citations: Calladine & Pate 2000; Mabberley, D.J. 1987; Raven, P.H., et al. 1981; personal observations.