Boxelder Maple - Acer negundo

Common name(s):  Boxelder Maple, Box Elder, Maple Ash
Scientific name:   Acer negundo
Family:    Soapberry family (Sapindaceae)
Native range:  North America
Type: Deciduous
Non-native range:  widely planted as an urban tree in cities and parks
Average height range:  10 - 25 meters
Forest or habitat:   Flood plains, riparian habitats
Wood density and quality:  
Leaf shape:  Odd pinnately compound (imparipinnate) with 3-7 leaflets
Leaf arrangement:  Opposite
Leaf margin:  Serrate
Leaf venation: Pinnate with alternating secondary veins, netted
Leaf stem:  4 - 8 cm (prior to first set of opposite leaflets)
Leaf surface:  glabrous (smooth, not hairy)
Inflorescence:  drooping raceme
Flower: staminate flowers on slender hairy pedicels,  inconspicuous
Male/Female:  dioecious (male and female are separate trees)
Fruit: double Samara pair
Edible?:  no
Seed description:  flattened disk-like with “wings” (samara)
Seed dispersal mechanism:  wind blown samara
Bark: Gray, furrowed
Traditional uses:  ornamental, shade
Commercial uses:  source of wood fibre
Invasiveness:  Australia (1), naturalized in parts of China (2)

(Staminate - male flowers)

(Pistillate - female flowers)

(winged "samara" seeds)

(Furrowed bark)

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1. http://www.hear.org/pier/species/acer_negundo.htm
2. http://en.wikipedia.org/wiki/Acer_negundo

Snowflake aralia - Trevesia palmata

This Snowflake Aralia tree (Trevesia palmata) is located in a botanical garden in the south of Spain. It is characterized by very large palmately lobed leaves with the individual lobes also being lobed. The leaf stems (petiole) are also quite long measuring about 75cm in length in some instances. The leaves themselves are about 50cm (30inches) across. The name "snowflake" for this tree most undoubtedly comes from the shape of the leaves which of some trees have a marked snowflake look.

The flowers are another dramatic feature of this tropical tree. They hang from long stems on the underside of the tree which makes them a bit less conspicuous but when seen from below they are quite impressive. The inflorescence is in the shape of an umbrel that forms a complete ball at the end of the peduncle (flower stem). They are about the size of a softball (10-12 cm in diameter)


The tree tends to have multiple trunks with small thorn like protrusions on the lower bark.