41 - Juglandaceae
from Division 5 - Magnoliophyta
Summary
Deciduous, monoecious trees. Leaves alternate, imparipinnate, without stipules. Flowers unisexual, epigynous, more or less actinomorphic. Male flowers in pedunculate catkins; bracteoles 2, rarely absent; perianth absent or small and 1- to 5-lobed; stamens 3 to many; filaments short; a rudimentary ovary sometimes present. Female flowers in pendulous catkins or one to few in a stiff cluster, in the axil of a bract; bracteoles 2; perianth small and inconspicuous, 1- to 5-lobed; styles 2; stigmas branched; ovary 1-celled, with 1 ovule. Fruit a drupe or winged nut; seeds without endosperm.
Contains about seven genera and over 60 species in the northern hemisphere, in temperate areas and on mountains in the tropics, and in South America.
Pith continuous; male catkins 3 or more together; perianth of male flowers absent or very small 2. Carya
Pith chambered; male catkins solitary; perianth of male flowers present 2.
Buds sessile, with scales; leaves aromatic; fruit a large drupe 1. Juglans
Buds stipitate, usually naked; leaves not aromatic; fruit a winged nut 3. Pterocarya
Juglans L.
Deciduous, monoecious trees. Twigs with chambered pith. Buds with scales, sessile. Leaves alternate, imparipinnate, aromatic. Flowers unisexual. Male flowers numerous, in solitary pendulous catkins; bracteoles 2; perianth absent or small and 1–5-lobed; stamens 4–40; filaments short; a rudimentary ovary sometimes present. Female flowers in erect terminal few-flowered spikes; bracteoles 2; perianth 4-lobed; stigmas 2, simple. Fruit a large indehiscent drupe; stone (walnut) incompletely 2- to 4-celled.
Contains about 15 species in north temperate regions, south-east Asia, Jamaica and Central and South America.
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- Flora of Great Britain and Ireland , pp. 314 - 317Publisher: Cambridge University PressPrint publication year: 2018