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Tree Flowers

Dirty trees 

tulip-tree, European linden,
honey-locust, red ash Norway maple and sweet-gum 

Tulip-tree (Liriodendron tulipifera, family Magnoliaceae) is a native forest giant sometimes planted in lawns, parks, and cemeteries. In late May it abundantly produces large flowers, superficially resembling those of tulips.

tulip-tree flower

Tulip-tree flowering.

 After flowering, the petals fall to the ground, looking like festive little pieces of ribbon.

tulip-tree petals

Tulip-tree petals on the ground, May 26, 2008, Union Cemetery, Columbus, Ohio..

European linden (Tilia europea, family Tiliaceae) is a commonly planted street tree, similar to our basswood (T. americana). It abundantly bears small yellow flowers in few-flowered clusters fused to a distinctive leaf-like bract. In late June, vast numbers of shed petals and spent stamens litter the ground beneath the trees, along with a few entire flower clusters.

linden flowers on the ground

European linden flower parts and flower clusters cover the ground, June 25, 2008, Columbus, Ohio.

linden flowers closeup

European linden flowers clusters on the ground, June 25, 2008, Columbus, Ohio.

linden flowers closeup

Closeup of European linden petals and stamens on the ground, June 25, 2008, Columbus, Ohio.

Honey-locust (Gleditsia triacanthos, family Caesalpinaceae) is a native tree that is often planted as a street tree partly because its teeny-tiny leaflets don't require raking. The female trees though can be pesky for sure, as the strap-shaped legumes gracefully adorn the streets and sidewalks beneath them.

heney-locust legumes

Honey-locust fruits grace the ground along North High Street in Columbus, Ohio, October 17, 2008.

honey-locust fruits

Honey-locust fruit, October 17, 2008, Columbus, Ohio.

Each tulip-tree flower produces many fruits of a type called a "samara," which is a one-seeded fruit that is winged for wind dispersal. Tulip-tree samaras, as well as those of various maple and ash species litter the ground in autumn and winter.

tulip-tree samaras

  Tulip-tree and Norway maple samaras on the ground, November 18, 2008, Columbus, Ohio..

ash and tulip-tree samaras

Red ash and tulip-tree samaras decorate the roadside, November 19, 2008, Columus, Ohio.

Sweetgum (Liquidambar styraciflua, family Hamamelidaceae) produces spiny globe-shaped multiple fruits that are clusters of many 1-2 seeded capsules.

sweetgum fruits

Sweetgum fruits are multiples of 1-2 seeded capsules.

Sweetgum is most noted for its tendency to litter the ground with the spiny balls, but careful observers (and goldfinches) are drawn to the seeds. Each capsule produces 1-2 winged seeds along with numerous small fragments of some mysterious corky material. Being winged, the seeds look a lot like small samaras but they aren't samaras because samaras are one-seeded fruits, not the seeds themselves, as these are.

sweetgum seeds

Sweetgum seeds and mysterious corky material packed with the seeds, December 7, 2008, Columbus, Ohio.

"Dirty trees" might be a nuisance at times, but that's a small price to pay for the fascinating glimpse they provide into the world of plant adaptations. Carbon sequestration is good too!