Volunteer(s) for Habitat Restoration!

By Matt Griffiths

No, not that kind of volunteer. I'm talking about vegetation. We've noticed a much higher survival rate of germinating seeds (or volunteers) of all types at Tucson Audubon's habitat restoration sites this year.

At the Simpson Farm site in Marana we guess that the main cause of this (among a host of other variables) is the first favorable amount of rain in at least two years! Winter seed germination of species such as saltbush has occurred at a pretty good rate recently, but survival of these volunteers has been very low to nonexistent. This year a fairly productive winter rainy season led to good germination and something approaching a more "normal" amount of summer rain (any water really! In reality it was roughly 4 inches) has allowed a great majority of the small plants to survive and actually flourish!

Desert saltbush volunteers in foreground surrounded by annuals

I've never seen anything like it in my six years of working at these sites. There are plants everywhere! Tucson Audubon has spent a lot of time spreading seed mixes of native trees, shrubs and grasses, and so far the output has been pretty sad. But things have changed! We spread seed at our new work area, the "Bowl" just this past fall and winter, and now the once barren sand flats are full of three kinds of saltbush and gramma grass along with naturally occurring annuals like purslane, false purslane, amaranth and wooly tidestromia. This growth followed a spring explosion of annuals also from our seed mix.

On top of this good news is the fact that already established plants (installed by Tucson Audubon and naturally occurring) are reseeding themselves at higher rates too. Once again the saltbush species are the stars of the show, but some tree species are also doing very well so far. Summer germinators such as velvet mesquite and paloverde have had a very productive season in low spots on our sites where soils have a higher clay content. It remains to be seen whether winter rains will be adequate enough to ensure the survival of these seedlings.

At Esperanza Ranch down in Santa Cruz county we've also seen a resurgence of giant sacaton this year. This is mostly the result of our seed mix but there's probably some reseeding going on here too. Look at this beautiful wall of wispy golden seedheads!

Giant sacaton at Esperanza Ranch

It's easy to see this year that a few good years of rain in a row could have a tremendous effect on the restoration efforts at these sites. Come on rain!

And, oh, if you're still reading and are interested in being the other kind of volunteer for Tucson Audubon, we have plenty of opportunities for you. There are field days coming up where you can get dirty and plant or remove invasives (Contact Kendall Kroesen). There's also a Volunteer Orientation on Sept. 29 where you can learn about all the ways to help us (Contact Becky Aparicio).

Here are some recent photos of the vegetative bounty this year.

Gramma grass (ID anyone?)

Tidestromia and purslane in the Bowl

Four-wing saltbush surrounded by volunteers of 3 saltbush species

Red-tailed Hawk using one of our perches

Velvet mesquite volunteers in Bowl

Devil's claw in Bowl

Sacaton and Santa Ritas, Esperanza Ranch

Raptor perch