Desert Blood Services will conduct a community blood drive tomorrow, Friday, October 31, at the Black Rock High School, 59273 Sunnyslope Drive in Yucca Valley, from 8 to 1. Donors must be at last 15 years old to give blood, and those aged 15 or 16 must have signed parental consent forms, available from any donor center. Donors will receive incentives. In addition, Desert Blood Services offers donors a mini-physical and free cholesterol screening with every blood donation.