Work begins today on the first trails of the Pittsburgh Botanic Garden in North Fayette and Collier.

This is the first of four scheduled sessions in which volunteers will clear invasive plants on the 454-acre site adjacent to Settler's Cabin Park. The trails will ultimately run though the Temperate Forests of the World, five woodland gardens covering 30 acres. The first trail being constructed will be a mile long with a lower wildflower trail.

The other clean-up days are Sept. 11 and 25 and Oct. 9. Work will run from 9 a.m. to noon each day. To volunteer or for more information, call Linda Shaytar at 412-444-4464.

Find out if your heirlooms are valuable treasures Sunday at the third annual "Pittsburgh's Hidden Treasures, An Antiques Appraisal Show" at the Senator John Heinz History Center in the Strip District.

KDKA-TV will be taping the program from 10 a.m. to 4 p.m. as visitors meet with professional appraisers to determine their items' approximate monetary value. Segments will be included as part of a series of shows on KDKA-TV beginning this fall.

A rain barrel/watershed workshop will be held from 6:30 to 8 p.m. Sept. 8 at the CCI Center on the South Side.

Presented by the Pennsylvania Resources Council, the workshop will show how to make a rain barrel and includes the necessary hardware. Cost is $35 per person or $45 per couple. To register, call 412-431-4449, ext. 247. Information: www.prc.org.

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