Trees of Victoria: Pines

Pinus contorta banner

Pinus: Introduction

Pines are conifers in the Genus Pinus. They have relatively long needle-like leaves that are bound together in groups of two to five by a fascicle (Fig. 1, Fig. 2). The female cones are woody and have spirally-arranged scales that each hold two seeds. Generally the mature cones open to release their seeds while on the tree, however, some cones only open when exposed to fire (serotinous cones)(Fig.3).

Pine cones have woody scales that radiate in a helical pattern from the central axis of the cone. When the cone is closed (Fig. 4), the exposed portion of the scale is called the apophysis (Fig. 5). The raised central portion of the apophysis is the called the mucro and the central portion of the mucro is the called the umbo which often has a prickle.

A cluster of pine needles
Figure 1. A cluster of pine needles.
a fascicle of pine needles.
Figure 2. A fascicle is a papery wrap that binds pine needles into a bundle.
A serotinous pine cone.
Figure 3. A serotinous pine cone that will remain closed until exposed to fire (Pinus pinaster).

A typical pine cone.
Figure 4. A typical closed pine cone with prickles on the umbos.

A closeup of a pine cone scale showing location of the apophysis, mucro, and umbo.
Figure 5. A pine cone scale showing the location of the apophysis, mucro, umbo, and the transverse ridge.

Pines: Two needle pines

A. In our study area pines will have either two, three, or five needles in a fascicle (Pines Key 1). The majority of pines in Victoria are two needle pines (Fig. 6).

a dichotomous key to pine tree identification
Pines Key 1. Identification key to Pine species.

Pinus nigra needles showing  two needles in  a fascicle.
Figure 6. Pinus nigra, showing two needles per fascicle.

Pines with needles less than 60mm long.

B. C. Of the trees with needles less than 60mm long, one species has extensive orange flaky bark on the upper trunk and branches. This species is the Scotts Pine (Pinus sylvestris) (Fig. 7, Fig. 8).

A Scotts Pine showing orange coloured bark on the trunk
Figure 7. A Scotts Pine showing orange bark on the trunk.
Scots Pine bark
Figure 8. Scotts Pine bark.

D. To determine the difference between Jack Pine (Pinus banksiana) and Shore Pine (Pinus contorta) examine the shape of the cones and their orientation on the branchlets. Jack Pine has unique curved horn-shaped cones (Fig. 9) that are attached so that their ends point toward the end of the branchlet (Fig. 10). Pinus contorta cones are not curved (Fig. 11), are armed with a sharp prickle, and tend to point perpendicular to the branch or towards the trunk of the tree (Fig.12).

Jack pine cones
Figure 9. Pinus banksiana cones.
Jack pine branchlet showing cones that point toward end of branch
Figure 10. Pinus banksiana branch with cones that point toward the end of the branch.

Shore Pine cones
Figure 11. Pinus contorta cones.
Shore Pine branch and cones
Figure 12. Pinus contorta branch showing cones that point toward the trunk.

Cones with prickles and needles longer than 160 mm.

E. F. We only have one two-needle pine that has cones with prickles and needles longer than 160 mm, the Maritime Pine (Pinus pinaster). The cones of this species are serotinous, glossy orange-brown and 70-250 mm long (Fig. 3). For details of this species and it's identification follow this link: Pinus pinaster.

Cones with prickles and needles shorter than 160 mm.

G. Among the pines with needles less than 160mm and cones with prickles, some have distinctive orangish flaky bark (Fig. 8) like the Scotts Pine. Pinus clausa, the Sand Pine is a very rare species in Victoria, with only one known occurrence. Pinus densiflora the Japanese Red Pine is more common, both share orangish flaky bark, but differ in the position of the resin canals. The Sand pine has median resin canals, while the Japanese Red Pine has marginal resin canals.

The two-needle pines with needle lengths greater than 160mm and black or gray bark, are the Austrian Black Pine (Pinus nigra) and the Japanese Black Pine (Pinus Thunbergii). The Austrian Black Pine is one of the most common pines planted in Victoria. When mature, its buff-yellow mature cones are a good characteristic to look for, while the Japanese Black Pine has brown-gray cones. In the spring the Japanese Black pine has striking long white terminal shoots that look like candles (Fig. 13).

Pinus thunbergii candles
Figure 13. Pinus thunbergii in spring showing white elongated shoots.
Two-needle pines with needles longer than 60mm and cones with no prickles.

H. The final two species of two-needle pines have no prickles on their cones. The species with needles greater than 120mm and brittle needles is the Red Pine (Pinus resinosa). The species with needles less than 120mm and more flexible needles is the Aleppo Pine (Pinus halapensis).