Oracle, Arizona, Invasive Plants

Invasive Plants

Pennisetum ciliare - Buffelgrass
A clump-forming, sprawling, African import that grows 1' to 1.5' tall and is considered extremely invasive and undesirable. It has branching stems and 1/4" wide leaves that are rough if a finger is run down the flat of the leaf. At the intersection of leaf and stem are noticeable thin long hairs, a trait not found in Fountain Grass or Red Brome grass. Fat, reddish, bottlebrush flower spikes, 1.5" to 5" long, on top of rough-feeling stalks turn tan with age. Blooms quickly after light rains. Roots out-compete native plants for moisture and nourishment and re-sprout after a fire. Eradication is accomplished by prying the entire plant and its roots out of the ground.

The links below, for Internet Explorer, are a video produced by Sonoran Desert Weedwackers to help you identify and remove buffelgrass.

Click on this 5 MB link only if you have a high speed or DSL Internet connection:
• Buffelgrass Eradication 5 MB video

Using a standard dial-up phone line, this low resolution video could take up to half an hour to download:
• Buffelgrass Eradication low resolution 1.3 MB video

Asphodelus fistulosus: Onionweed
Onionweed is a European import and a prolific seeder that crowds out native species. It has flowers with six pale pink petals and a brown vertical line down the center of each petal.
Onionweed, however, resembles a desirable Arizona native plant,
Allium macropetalum: Desert Onion. Here is how to tell the difference:

Onionweed grows to as much as 30" high. Its petals tend to be somewhat flat, as can be seen by the pictures on the left.

Desert Onion grows to no more than 8" high. Its flowers tend to be slightly cupped at the base with petal tips curved outward.

So the rule is — if the plant is taller than 8" — get rid of it fast.