About this Event
The Work
McGrew Spring is a secluded, shady oasis in southern Arizona's beautiful Whetstone Mountains. Closed to the public, the spring is more than two miles from any other water source and is a favorite haunt of coatis, black bears, mountain lions, coyotes, and birds. The spring is at about 4,500 feet elevation, and there is a 20-minute walk to access the site.
Unfortunately, in recent years, McGrew Spring has become overtaken by an invasive plant called horehound growing around the spring due to trespassing cattle. As of December 2022, we've completed restoring the cattle-exclosure fencing while also making it wildlife friendly, thanks to our volunteers' hard work! On this outing we'll be removing any remaining invasive plants.
What to Expect/Bring
- Bring a few water bottles (3L) for the day. We will have water at the truck, but that's a 20-minute hike away from where we're working.
- Bring plenty of snacks and a lunch.
- Bring work clothes and appropriate close-toed shoes that you don't mind getting dirty and potentially torn.
- Bring sun protection: sunscreen, long-sleeves, hat, etc.
- Bring warm clothes, rain jackets, etc. depending on the forecasted weather.
Getting There
Upon arriving to Kartchner Caverns State Park, let the ranger at the park entrance know that you're volunteering with SIA out at McGrew Spring.
Option 1
Meet at the SIA Tucson office at 3127 N Cherry Ave. to caravan or carpool to the field site at 6:45 a.m.
Option 2
Meet at the Guindani Trailhead parking area at Kartchner Caverns State Park at 8 a.m.
Trip Logistics
- 6:45 a.m. — meet with SIA staff at our office to carpool
- 8 a.m. — meet at Kartchner Caverns State Park and hike for about 20 minutes to McGrew Spring.
- 4 p.m (or earlier) — finish up for the afternoon and then head back to the Guindani Trailhead parking area.
Unfortunately, pets are not allowed on this trip.
The trailhead parking has flush toilets, but there are no other facilities available on this trip.
If you have any questions, please contact Sarah at [email protected].
Event Venue & Nearby Stays
Kartchner Caverns State Park, 2980 Arizona 90, Benson, United States
USD 0.00



