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Poaceae
(Grass family)

Monocot

Wheat Plant

Shoots

Leaf

  • Start at nodes, first as a sheath that wraps around the stem, and extends into a long blade

  • ​Leaves have parallel veins

  • Growth- New leaves grow in layers inside older leaves

Stem

  • Typically hollow, while nodes (joints) are solid

  • May spread using stolons (above-ground runners) or rhizomes (underground stems), which can produce new shoots

Storage

  • Underground Storage Organs (USOs)

    • Rhizomes​

    • Tubers

    • Corms/Bulbs

  • Cellular Storage

    • Parenchyma​

    • Endosperm

    • Fusoid cells

Growth

  • ​May spread using stolons (above-ground runners) or rhizomes (underground stems), which can produce new shoots

Roots

Root types

  • Primary Root: The initial root from the seed.

  • Seminal Roots: Early roots from the embryo.

  • Crown Roots: Adventitious roots from underground stem nodes, crucial for establishment.

  • Brace/Stilt Roots: Adventitious roots from above-ground nodes, like in corn

Roots

  • Dense, fibrous system of adventitious roots that grow from stem nodes, instead of a taproot

  • Forms a bushy network that spreads near the soil surface to hold soil and absorb water/nutrients

Flowers

Stamens

Lily_stamens_edited_edited.png

  • Typically 1-3, featuring large anthers that produce abundant pollen

Pistil

a close up of a pink flower with drops o

  • Simple, with a large, bushy stigma (to catch windblown pollen)

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Ovary

  • Superior ovary

  • Irregular and reduced (simplified) as an adaptation for wind pollination

  • Most are hermaphroditic, though some, like corn, are monoecious.

  • Arranged in an inflorescence called a spikelet, which contains smaller units called florets

    • Each floret is enclosed by 2 bracts: the lemma and the palea

    • The entire spikelet is enclosed by another pair of bracts called glumes

Sepals
(​Calyx)

  • Absent, or reduced to 2 small scales called lodicules

  • Absent Corolla

Flowers

Fruit

Fruits

Flower Branch_edited.png

  • Usually a dry caryopsis commonly known as a grain

Did you know?

  • It is the fourth largest plant family – contains approximately 600 genera and 10,000 species

Photos

Whole Plant

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Variations

sorghum-01

sorgum

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Bamboo

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Wheat

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Rice

barley

Barley

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Oats

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Lawn Grass

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