The genus Rhus, commonly known as sumac, includes species valued as a food source and spice, offering a bright, lemony tang to beverages and dishes. Before harvesting, it is necessary to confirm the plant’s identity, as some sumac relatives are toxic. This guide provides steps for safely identifying edible varieties, selecting the best time for collection, and properly preparing the harvest for culinary use.
Safe Identification of Edible Sumac
Distinguishing edible sumac species from the toxic Poison Sumac (Toxicodendron vernix) is essential. Edible varieties, such as Staghorn (Rhus typhina), Smooth (Rhus glabra), and Dwarf (Rhus copallinum), produce fruits in dense, upright, cone-shaped clusters called drupes. These drupes are always a vibrant red color and are covered in fine, velvety hairs.
Poison Sumac is differentiated by three distinct features: fruit color, cluster appearance, and habitat. Its berries are smooth, waxy, and ripen to a creamy white or greenish-white color, never red. These clusters hang loosely and droop, unlike the upright cones of edible species.
Poison Sumac prefers to grow exclusively in very wet environments like bogs, swamps, and marshy areas. Edible sumacs, by contrast, thrive in dry, open habitats such as roadsides, fields, and hillsides. The leaves of edible sumac also have serrated edges, while the leaflets of Poison Sumac have smooth, entire margins.
Optimal Timing for Harvesting
Harvesting sumac at the right moment ensures the highest concentration of the flavorful malic acid on the drupes. The optimal time for collection is generally from late July through early autumn, often peaking in August or early September, depending on your geographic location. The berries should be fully mature and exhibit a deep, bright red color.
Ensuring the drupes are completely dry at the time of harvest is essential for preserving the tart flavor. The acidic compound responsible for the lemony taste is highly water-soluble, and heavy rains can wash this coating away.
Plan your harvest after a dry spell, ideally several days after any significant rainfall. Inspect the clusters for signs of mold or insect colonization, such as “worm poop,” which indicate the drupe is past its prime. Select only the freshest, brightest, and driest cones.
Step-by-Step Collection Method
Once you have identified an edible sumac stand in a clean area away from heavy road pollution, you can begin collection. Although the plant is not toxic, wearing long sleeves and gloves is helpful, as the branches of Staghorn sumac can be prickly.
Use clean and sharp tools, such as pruning shears or strong scissors, to ensure a clean cut. The goal is to harvest the entire cone, or “bob,” without damaging the main structure of the plant. Snip the cluster one to two inches below the base of the fruit cone, right where the cluster meets the woody branch.
Avoid cutting into the main, thick, woody stem of the shrub. Cutting just the fruit cluster allows the shrub to continue its growth cycle. Transport the harvested clusters in a breathable container, such as a paper bag or a wicker basket, to prevent moisture buildup that could encourage mold or wash away the flavor.
Cleaning and Curing the Harvest
Do not wash the sumac drupes with water, as this will dissolve the malic acid coating. Instead, gently shake each cone to dislodge dust, small insects, or loose debris.
The next step is curing, or thoroughly drying, the clusters to prevent mold and prepare them for grinding. You can dry the whole cones by spreading them in a single layer on a tray or by hanging them upside down in a sheltered, warm, dry, and dark location. Alternatively, use a food dehydrator set to a low temperature, around 135°F (57°C), until the berries are brittle.
Once dried, process the berries into a spice by gently rubbing or crushing them to separate the outer coating from the hard inner seed. Pulse the dried berries in a spice grinder or blender until the red “fuzz” separates from the seeds. The mixture is then passed through a fine-mesh sieve to separate the tangy red powder from the seeds and woody material, resulting in the final, ready-to-use spice.