There's only one problem with autumn -- it's too short. So if you want to take full advantage of the season while the temperature's right, check out one or more of the fall festivals in the area this weekend:

* Sully Plantation in Chantilly celebrates Harvest Days this Saturday and Sunday. There'll be crafts and food for sale, Sully House tours and plenty of musical entertainment. Hours are 11 to 5 each day. Admission is $3, $1 for children under 16. Call 437-1794 for directions and information.

* The 18th Annual Autumn Glory Festival in Oakland, Md., is this Friday, Saturday and Sunday, complete with a bluegrass concert Friday at 8 at Southern Middle School ($3, $2.50 for children); the Grand Feature Parade at 2 Saturday in downtown Oakland; the Maryland Fiddler's Championship Saturday at 8 at Southern High School ($4, $3.50 for children); and antique and crafts sales throughout the weekend. 301/334-3888; free admission.

* The City of Fairfax holds its Fall Festival this Saturday from 11 to 5, with free hay rides and scarecrow-making, and food and crafts for sale. The festival is at Main Street and University Drive. 385-7858.