Flower:

Flowers are borne in structures called cones (strobili) with separate male and female cones on the same tree. Male (pollen) cones are cylindrical with rounded tips, ½ to ¾ inch long, in dense clusters at the base of new branchlets (candles) with the newly expanding bud just above. The female strobili form at the tips of the new candle and are small and roundish, often deep pink to purple colored.

Leaves and bark:

Leaves are needle-like, 4 to 7 inches long, in bundles of two that spiral up around the branch. The pair stays closely aligned, rounded on the outside but facing surfaces flattened (D shaped in cross section), mostly straight or obscurely twisted. The needles break cleanly when bent.

New twigs are reddish brown and shiny, sometimes covered with sticky resin, soon turning reddish or dull grayish brown. Buds are orange or reddish brown with loose scales and a sharp point. The bark becomes grayish brown with patches of reddish orange and loose, scaly, vertical plates with darker furrows between.

Branch buds are large, around 1 inch long with a long sharp tip; bud scales are narrow, lance shaped, loose with papery margins.

Fruit:

The fruit is a hard cone, small and egg shaped, 3/8 to ½ inch long at the end of the first season, 1½ to 2¼ inches long when mature, the tips of the scales without a barb.

Notes:

The Minnesota State tree, Red Pine is a massive northern forest tree with a dbh (diameter at breast height) of over 3 feet, like the White Pine (Pinus strobus), most of our large, old growth stands were cut down over a century ago. While modern forest management practices do not favor its natural regeneration, it is heavily planted in plantations easily recognized by their straight, linear rows. Where these plantations have been extended out into drier prairie habitats, the trees rarely attain great stature before succumbing to native pine bark beetle infestations after a few hot, droughty years. Most similar is Austrian Pine (Pinus nigra), an urban landscape tree that also has needles bundled in pairs, but the needles do not break cleanly when bent, where those of Red Pine do, and the bark of Austrian Pine does not typically have the orangish plates. Red Pine is sometimes referred to as Norway Pine, a misnomer since the species did not originate in Norway.