WHITE CITY — Ecologists will be using fire Wednesday through grasslands and around vernal pools near White City to help native plants and habitat — but without cooking rare fairy shrimp — during a 100-acre controlled burn.

The burn is primarily to maintain and restore native prairie habitat at The Nature Conservancy's 54-acre Agate Desert Preserve at the corner of Table Rock Road and West Antelope Road in White City, according to the conservancy.

Another 50 acres of land north and west of the preserve that is owned by the city of Medford and the Medford Water Commission are also tapped for burning, in part to curb wildfire threats and to help vernal pool restoration there.

The preserve contains some of the highest quality mounded prairie and vernal pool habitat left in the Rogue Valley and sports rare native grasses, threatened vernal pool fairy shrimp and two endangered wildflowers — Cook's desert parsley and large-flowered woolly meadowfoam.

The fire will knock out non-native starthistle and medusahead plants, help jump-start native seeds and stimulate flower bulbs while the shrimp eggs are incubating in the ground, says Molly Morison, the conservancy's southwest Oregon preserve manager.

This is the fifth time since 1989 that the conservancy has introduced fire into the preserve, and each time the grasses and flowers thrive in their cleansed environment, Morison says.

"We've even burned through the vernal pools before and the shrimp did fine," Morison says.

The shrimp eggs are now "resting" in the sediment and are extremely resistant to heat and drought, Morison says.

Under a somewhat rare burn permit on the Rogue Valley floor during wildfire season, crews from the conservancy and the Ashland-based Lomakatsi Ecological Services will ignite and monitor the flames during the afternoon burn, which is expected to dissipate in less than four hours, according to the conservancy.

The burn will not take place unless winds are favorable, it's not expected to exceed Oregon air-quality standards, and the smoke is expected to disperse quickly, Morison says.

"The smoke should just go up and get carried out of the valley," Morison says.

Traffic-control and information points will be set up on Table Rock Road and east and west Antelope roads, she says.

A wet spring kept the conservancy from conducting the burn earlier because the grasses and targeted non-native plants were not dry enough, Morison says. Measurements taken Tuesday afternoon showed the site is ready, she says.

Jackson County Fire District 3 spokeswoman Ashley Lara says burn permits within fire season are somewhat rare, but the conservancy worked with state agencies on a plan that proved doable.

"We like to work with our partners to get projects done," she says.

Morison says a similar burn was conducted in fall 2011 within wildfire season because of a wet spring that year.

— Reach Mail Tribune reporter Mark Freeman at 541-776-4470 or mfreeman@mailtfribune.com. Follow him on Twitter at www.twitter.com/MTwriterFreeman.