Leaves of three, let them be!
Poison Oak (Toxicodendron diversilobum) can resemble a climbing vine, a shrubby bush, or a small tree. In open areas under full sunlight, it usually forms a dense leafy shrub about one to six feet in height. In shaded areas it takes the form of a much taller climbing vine, supporting itself by means of aerial roots. The compound leaves come in clumps of threes, the larger middle leaflet having a distinct stalk, and the other two being alternate, the leaves themselves also are alternate on the stem. The leaves are lobed, generally a dark shiny green in the Summer and red or orange in Autumn. Since it is deciduous woody plant, in Winter it can look like nothing more than bare sticks coming from the ground. Avoid at all costs!