Bryan's Field sits between Middle Run Trail and Whitely Farms. There is a spur indicated in the map that heads Southeast (towards the road) for about 25 yards and then crosses under the road in a huge drainage pipe towards Middle Run Trail. Take the connector northwest to tack on Whitely Farms.
Like most of the trails in the area, Bryan's Field is well-groomed singletrack. Packed dirt with a few roots and some rocks to negotiate.