This Summer I was fortunate to take a hike with Mickey Long, who supervises natural areas for LA County Parks and Recreation. I asked him to join me at one of the more depressing spots in the Angeles Forest front country--the trail from Chantry Flat to Stuartevant Falls.

Although we spotted a number of wildflowers along the fire road descending into Big Santa Anita Canyon--including indian pinks and native delphinium (both pictured below)--we sampled a Smorgasbord of weeds: annual grasses, Spanish broom, euphorbia, arundo, bladder senna, eucalyptus, even rock roses. "Aesthetically there's something missing from the landscape," said Long, "both in form and function. The danger here is,

even though we're seeing plenty of native plant habitat, if a fire comes through, the weeds will get the upper hand."

Long pointed out Western Fence and whiptail lizards, hunting for bugs in the underbrush. He said the non-native grasses don't support the variety of insects that the native plants do.

Things didn't get any more cheerful when we arrived at the stream.

English ivy blankets 3.5 miles of stream bank.

Cabin owners planted the ivy decades ago and it's run amok. To keep the alders alive, they clip it off of the trunks. But the ivy (with a little help from some Himalayan blackberry) has crowded out most of the native plants. On a subsequent trip I counted only three Humboldt lilies (pictured up top) persisting along the stream.

Long said no one has studied the effect of the ivy infestation on native animals, but "there's not too many ways this could be beneficial to a native animal." Amphibians need to be able to move from the stream where they breed and to the adjacent hillside where they burrow. "They need to feed as they move around, and I don't know what food sources are left under there."

You can learn more about garden plants that threaten wildlands in these stories I reported for KPCC-FM.