# Black Alder (*Alnus glutinosa*) Black Alder is a strong tree that grows near water! It has dark bark and can provide a home for many critters. - **Category:** [Trees](https://www.snappit.app/explore/categories/tree) - **Rarity:** Common - **Danger:** 1/5 · Very low - **Snaps:** 3 - **Habitat:** Wetlands and riverbanks - **Also known as:** Common Alder, European Black Alder ![Black Alder](https://res.cloudinary.com/drieglelr/image/upload/v1771424394/objects/4815.jpg) ## Appearance The Black Alder has dark, deeply fissured bark and distinctive roundish, somewhat sticky green leaves. It produces long, purple-brown male catkins and small, cone-like fruits that persist on the branches, giving it a unique look, especially in winter. ## Taxonomy - **Kingdom:** Plantae - **Phylum:** Tracheophyta - **Class:** Magnoliopsida - **Order:** Fagales - **Family:** Betulaceae - **Genus:** Alnus ## Interesting facts - Alder cones are like mini Christmas decorations that stay on the branches all winter long! - Its super durable wood was used to build Venice, as it lasts almost forever underwater! - Look closely, its leaves stay green and never turn vibrant autumn colors before falling! - These trees release huge clouds of tiny pollen in spring, making the air look hazy! ## Special abilities - **Nitrogen Factory:** Black Alder can enrich the soil with nitrogen using special root bacteria, making the ground more fertile for other plants to grow. - **Water Loving Roots:** Black Alder has roots that thrive in waterlogged soil, helping it grow strong in damp places where many other trees struggle. - **Underwater Woodpower:** Black Alder's wood becomes incredibly tough and resistant to rot when submerged in water, making it last a long time. ## Measurements & details - **Height:** 15-25 m - **Spread:** 6-12 m - **Edible:** No - **Size:** 40-100 cm - **Lifespan:** 60-120 years - **Fruit Type:** Strobile (woody cone) - **Growth Rate:** Medium - **Leaf Type:** Deciduous ## Ecological connections - **Symbiotic with:** Frankia bacteria (*Frankia alni*) — helps fix nitrogen in its root nodules - **Eats:** [Eurasian Siskin](https://www.snappit.app/explore/eurasian-siskin) (*Carduelis spinus*) — enjoys feeding on the tree's abundant small seeds - **Eats:** [Alder Leaf Beetle](https://www.snappit.app/explore/alder-leaf-beetle) (*Agelastica alni*) — larvae and adults feed on the tree's leaves - **Shelter:** [Eurasian Otter](https://www.snappit.app/explore/eurasian-otter) (*Lutra lutra*) — often uses alder-lined riverbanks for denning ## Traits - [Deciduous](https://www.snappit.app/explore/traits/deciduous): Deciduous plants periodically shed all their leaves, typically during autumn or dry seasons. - [Shade Tolerant](https://www.snappit.app/explore/traits/shade-tolerant): Shade tolerant plants are adapted to grow and thrive in areas with low light levels, requiring less direct sunlight. - [Broadleaf Tree](https://www.snappit.app/explore/traits/broadleaf-tree): Broadleaf trees are angiosperms characterized by flat, wide leaves that are typically shed annually in temperate climates. - [Rapid Growing](https://www.snappit.app/explore/traits/rapid-growing): Rapid growing plants exhibit accelerated growth rates, quickly increasing in size and biomass within a short period. - [Wetland](https://www.snappit.app/explore/traits/wetland): This habitat trait identifies species found in wetlands, which are areas of land saturated with water, either permanently or seasonally, including marshes, swamps, and bogs. ## Collections - [Trees](https://www.snappit.app/explore/collections/trees) ## Safety **Danger:** 1/5 · Very low Do not pick or eat anything you find. Some plants and mushrooms can be harmful. ## Frequently Asked Questions ### How to identify Black Alder? Compare leaves or needles, how they attach to the twig, buds, bark and the shape of the crown. Lobed leaves are useful clues, but several unrelated trees share a similar outline. Tree Identifier: upload a photo and compare the visible details. ### How tall is Black Alder? 15-25 m ### How wide does Black Alder spread? 6-12 m ### Is Black Alder edible? No ### How big is Black Alder? 40-100 cm ### How long does Black Alder live? 60-120 years ### Where is Black Alder usually found? Wetlands and riverbanks ### What kind of fruit does Black Alder produce? Strobile (woody cone) ## Where to spot - [Dresden Island Lock and Dam Historic District](https://www.snappit.app/guides/places/dresden-island-lock-and-dam-historic-district) — Illinois, US · Historic District - [Matthaei Botanical Gardens](https://www.snappit.app/guides/places/matthaei-botanical-gardens) — Michigan, US · Botanical Garden - [Biosphärenreservat Thüringer Wald](https://www.snappit.app/guides/places/biospharenreservat-thuringer-wald) — Thüringen, DE · Park - [Biosphärenreservat Spreewald](https://www.snappit.app/guides/places/spreewald-biosphere-reserve) — Brandenburg, DE · Park - [Naturpark Harz/Sachsen-Anhalt (Mansfelder Land)](https://www.snappit.app/guides/places/naturpark-harz-sachsen-anhalt-mansfelder-land) — Sachsen-Anhalt, DE · Park - [Naturpark Holsteinische Schweiz](https://www.snappit.app/guides/places/naturpark-holsteinische-schweiz) — Schleswig-Holstein, DE · Park [View all places to see Black Alder](https://www.snappit.app/guides/where-to-see/black-alder) ## More Trees - [English Oak](https://www.snappit.app/explore/english-oak) (*Quercus robur*) - [Sessile Oak](https://www.snappit.app/explore/sessile-oak) (*Quercus petraea*) - [Northern Red Oak](https://www.snappit.app/explore/northern-red-oak) (*Quercus rubra*) - [White Oak](https://www.snappit.app/explore/white-oak) (*Quercus alba*) --- Source: [Black Alder: Facts & Places to See — Snappit](https://www.snappit.app/explore/black-alder)