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Pseudotsuga macrocarpa, commonly called the bigcone spruce or bigcone Douglas-fir, is an evergreen conifer native to the mountains of southern California.It is notable for having the largest (by far) cones in the genus Pseudotsuga, hence the name.
The knobcone pine, Pinus attenuata (also called Pinus tuberculata), [2] is a tree that grows in mild climates on poor soils. It ranges from the mountains of southern Oregon to Baja California with the greatest concentration in northern California and the Oregon-California border.
Many Pinus species adapted to this fire-prone environment with serotinous pine cones. A set of conditions must be met in order for long-term seed storage to be evolutionarily viable for a plant: The plant must be phylogenetically able (pre-adapted) to develop the necessary reproductive structures; The seeds must remain viable until cued to release
A mature female big-cone pine (Pinus coulteri) cone, the heaviest pine cone A young female cone on a Norway spruce (Picea abies) Immature male cones of Swiss pine (Pinus cembra) A conifer cone, or in formal botanical usage a strobilus, pl.: strobili, is a seed-bearing organ on gymnosperm plants, especially in conifers and cycads.
The seeds are 2–3 cm (3 ⁄ 4 – 1 + 1 ⁄ 4 in) long, with a thick shell, with a vestigial 1–2 mm (0.04–0.08 in) wing; the seedlings have 18–24 cotyledons, the highest number reported for any plant. It differs from all other pinyon species in that it has very massive cones and large seeds.
In some cases, they will drop their seeds, but in most Pinus serotina, they will persist and hold their seeds. The color of the seed cones and seed scales is red-brown in color. The foliar sheaths measure 0.4 to 0.8 with long bases. The seeds are ovule in shape, being 0.2 and 0.24 in length, and have an angled tip colored a pale brown. [10]
Pinus pungens is a tree of modest size (6–12 metres or 20–39 feet), and has a rounded, irregular shape. The needles are in bundles of two, occasionally three, yellow-green to mid green, fairly stout, and 4–7 centimetres (1 + 1 ⁄ 2 –3 in) long.
The seed cones are green, 6–12 cm (2.4–4.7 in) long and 5–10 cm (2.0–3.9 in) in diameter, and mature about 18–20 months after wind pollination. They disintegrate at maturity to release the seeds which are small and brown, thin and papery with a wing around the edge to aid wind-dispersal. [ 3 ]