Ober Savanna is a marvelous black oak sand savanna remnant of about 90 acres. There are no formal trails, but an informal path heads north from the minuscule parking area into the preserve interior. As with many savannas, it is usually easy to get around in the open understory beneath the oaks, especially if there’s been a controlled burn in the last few years. There is little poison ivy and biting insects are usually tolerable. However, a very busy train track cuts through the preserve, so be extra careful when crossing the tracks if you choose to explore the northern portion. Those trains run fast.
Grasses and many species of wildflowers are present throughout in the understory, attracting butterflies and other insects. One prominent wildflower is lupine. Lupines have compound leaves, each with seven to eleven leaflets arrayed in a whorl that radiates from the center of the leaf. Each plant has several leaves and, when flowering, a long central stalk that bears an array of blue or purple flowers, though sometimes they are white or partially white. Whatever their color, lupines put on an excellent show in season. After ripening, the black seed pods rattle in the wind or when brushed by passers-by.