The Bureau of Land Management is among the federal agencies celebrating National Public Lands Day on Saturday. That includes seven volunteer efforts in Arizona -- among them, pulling buffelgrass, restoring trails and picking up trash.

"There’s always a lot of volunteer activities, but this is the special designated day where BLM, along with other federal agencies, celebrate the largest hands-on volunteer effort across the country," said Deborah Stevens of BLM in Arizona.

Stevens said as many as 200 people in Arizona typically take part inthe volunteer activities.

"Volunteers are extremely valuable to us, because they do a great service to the public, to maintain these areas and keep them pristine for their use at any time. So yes, we do value volunteer support, because it does help us augment our funding," Stevens said.

Read the complete list of volunteer activities, and find out how to volunteer.