# Sourwood (*oxydendrum arboreum*) Sourwood, also known as the sorrel tree, is a deciduous understory tree native to the eastern United States, particularly renowned in the Appalachian region. Celebrated for its striking late-summer blooms and brilliant autumn foliage, it is a standout species in deciduous forests, where it rarely exceeds moderate heights. It is highly prized by beekeepers, as its delicate white bell-shaped flowers yield an incredibly rich, light-colored honey with a distinctively sharp, sweet flavor. Its sour-tasting leaves, which contain oxalic acid, give the tree both its common and scientific names. - **Category:** [Plants](https://www.snappit.app/explore/categories/plant) - **Rarity:** Common - **Danger:** 1/5 · Very low - **Snaps:** 3 - **Habitat:** Found in well-drained, acidic soils of upland deciduous forests, ridges, and slopes, often growing alongside oaks and pines. ![Sourwood](https://inaturalist-open-data.s3.amazonaws.com/photos/355230626/medium.jpg) Photo: Douglas Goldman, CC BY-SA 4.0 · [iNaturalist](https://www.inaturalist.org/photos/355230626) ## Appearance Sourwood typically grows 9 to 15 meters tall, featuring a slender trunk and a rounded canopy. Its bark is thick, deeply furrowed, and gray-brown, resembling alligator skin on older specimens. The leaves are oblong, finely serrated, and a glossy green during spring and summer, turning a breathtaking brilliant crimson to purple in early autumn. In mid-to-late summer, the tree produces drooping panicles of small, white, urn-shaped flowers that resemble lilies-of-the-valley, which eventually dry into persistent woody seed capsules. ## Taxonomy - **Kingdom:** Plantae - **Phylum:** Tracheophyta - **Class:** Magnoliopsida - **Order:** Ericales - **Family:** Ericaceae - **Genus:** Oxydendrum ## Interesting facts - Mountain hikers sometimes chew on the leaves to alleviate thirst, as the sour taste stimulates saliva production. - Sourwood honey is highly prized and rare because the trees bloom for only a short period in mid-summer, requiring beekeepers to time their hive placements perfectly. - The common name 'Sourwood' and scientific name 'Oxydendrum' (sour wood in Greek) both refer to the acidic, sour taste of the leaves. ## Special abilities - **Acidic Sap Defense:** The leaves contain oxalic acid, giving them a sour taste that deters many generalist herbivores and insect pests. - **Late-Season Blooming:** Unlike most forest trees, it blooms in mid-to-late summer, avoiding competition for pollinators and providing a vital late-season nectar source. - **Vibrant Autumn Adaptation:** Rapidly produces anthocyanin pigments in autumn, protecting its leaves from light damage as it resorbs nutrients before shedding. ## Measurements & details - **Length:** 900-1800 cm - **Lifespan:** 100-200 years ## Diet & Feeding As a photosynthetic plant, sourwood produces its own energy using sunlight, carbon dioxide, water, and essential nutrients absorbed from acidic soil. - **Primary Foods:** Sunlight, Water, Carbon dioxide, Soil minerals - **Foraging Method:** Photosynthesis ## Ecological connections - **Mutualism:** Honeybee (*Apis mellifera*) — Bees pollinate the flowers while harvesting nectar to produce famous sourwood honey. - **Host plant:** [Cecropia Moth](https://www.snappit.app/explore/cecropia-moth) (*Hyalophora cecropia*) — The caterpillars of this giant silk moth feed on the leaves of the sourwood. - **Eaten by:** [White-tailed Deer](https://www.snappit.app/explore/white-tailed-deer) (*Odocoileus virginianus*) — Deer browse on the twigs and leaves of sourwood, especially during the winter. ## Safety **Danger:** 1/5 · Very low No special safety notes yet. ## Frequently Asked Questions ### How to identify Sourwood? Start with the whole plant, then compare leaf arrangement, leaf edges, stems and any flowers or fruit. Opposite leaves grow in pairs; alternate leaves come one at a time along the stem. These details tell you far more together than a single green leaf does. Plant Identifier: upload a photo and compare the visible details. ### How long is Sourwood? 900-1800 cm ### How long does Sourwood live? 100-200 years ### What does Sourwood eat? As a photosynthetic plant, sourwood produces its own energy using sunlight, carbon dioxide, water, and essential nutrients absorbed from acidic soil. ### Where is Sourwood usually found? Found in well-drained, acidic soils of upland deciduous forests, ridges, and slopes, often growing alongside oaks and pines. ### How does Sourwood hunt? Photosynthesis ## Where to spot - [Arrowmont School of Arts and Crafts](https://www.snappit.app/guides/places/arrowmont-school-of-arts-and-crafts) — Tennessee, US · Campus - [Folly Lick Stream Valley Park](https://www.snappit.app/guides/places/folly-lick-stream-valley-park) — Virginia, US · Park - [Lake Fairfax Park](https://www.snappit.app/guides/places/lake-fairfax-park) — Virginia, US · Park - [The Gardens of the American Rose Center](https://www.snappit.app/guides/places/the-gardens-of-the-american-rose-center) — Louisiana, US · Botanical Garden - [Washington and Old Dominion Railroad Regional Park](https://www.snappit.app/guides/places/washington-and-old-dominion-railroad-regional-park) — Virginia, US · Park [View all places to see Sourwood](https://www.snappit.app/guides/where-to-see/sourwood) ## More Plants - [white snakeroot](https://www.snappit.app/explore/white-snakeroot) (*Ageratina altissima*) - [tree-of-heaven](https://www.snappit.app/explore/tree-of-heaven) (*Ailanthus altissima*) - [western sword fern](https://www.snappit.app/explore/western-sword-fern) (*Polystichum munitum*) - [common milkweed](https://www.snappit.app/explore/common-milkweed) (*Asclepias syriaca*) --- Source: [Sourwood: Characteristics, Facts & Places to See — Snappit](https://www.snappit.app/explore/sourwood)