True pines, as opposed to say, Norfolk Island-pine (Araucaria heterophylla) or Japanese umbrella-pine (Sciadopitys verticillata) are in the genus Pinus, which differs from other genera in the Pinaceae family. Other genera in the family include, for example, spruces (Picea), firs (Abies), and hemlocks (Tsuga).
One of the simplest ways of distinguishing pines from these other genera is that pines have needles in bundles of two, three, or five. Yes, there is an exception or two: for example, Pinus monophylla, the one- needled pine.
But Pinus monophylla grows out west, so for ID purposes we can focus on 2,3, & 5 needled pines. If needles are in bundles of 2, 3 or 5 – pine. If singly attached – not a pine. Note that the picture above has needles in bundles - it is a pine!
Common 2-needled pines include Scots pine (Pinus sylvestris), Austrian pine (Pinus nigra), and mugo pine (Pinus mugo).
The 3- needle pine we sometimes see out West include ponderosa pine (Pinus ponderosa), in Eastern arboreta and landscapes, the lacebark pine (Pinus bungeana), or in Eastern and southern forests, pitch pine (Pinus rigida) .
The five-needled pine we commonly see is the Eastern white pine, (Pinus strobus), but others sometime seen in eastern arboreta include limber pine (Pinus flexilis), the Swiss stone pine (Pinus cembra), and the bristlecone pine (Pinus aristata).
Expect more bygl-alerts on some of these pines, as well as different spruces and firs and hemlocks, but for now…
…Let us discuss the three-needled pine featured in this alert, which sometimes also has some bundles of only two needles. This pine was espied by a contingent of OSU Extension Nursery Landscape and Turf Team members enroute to their annual International Society of Arboriculture diagnostic workshop for the International Society of Arboriculture Conference in Washington, D.C.
Above, you saw cones of our mystery pine. Now for needles and cones, a look at the trunk, and a reminder of those needles.
Be the first to e-mail your ID of this pine, viewed in these accompanying pictures to email@example.com and – you will win a prize.
A note on bygl-alert prizes: the winner of last week’s prize: I wanted an image of true mistletoes is…well that will wait until my follow-up mistletoe alert: Soon.
Additional Note: Why do we care so much about all of this ID business? Because proper plant ID is Question #1 in the 20 Questions of Plant Problem Diagnostics. One example: Diplodia tip blight disease is a significant problem on 2-needled pines such as Scots, Austrian, and mugo pines, but only an occasional occurrence and very rarely a problem on white pine or on spruce.