Needle Dropping

Deciduous Conifers

• think with me
• for a moment
• about conifers
• those that readily come to mind are pines, spruces, and firs
• we know those ones as evergreens
• they have needles instead of leaves
• these needles are beneficial in that their smaller surface area prevents water loss
• which is great because conifers often times grow in arid regions
• they keep those needles year round too
• an evergreen conifer needle has a lifespan that’s 2 to 15 years long
• the cold, dry climate in which these trees usually live
• has a short growing season
• so instead of taking a large amount of time to regrow leaves every spring
• they can start photosynthesizing right away, the moment it gets warm

• but what about trees that drop their leaves?
• like maples, cottonwoods, and birches
• those trees are what we call deciduous
• they drop their leaves because maintaining them through the winter months takes far more energy than the trees have to give
• the leaves fall off in autumn
• the trees go dormant
• and then they put out new leaves come spring

• incredibly enough
• there are trees that are both conifers and deciduous
• how could this be?!
• well there are three main groups of deciduous conifers
• trees like larch, baldcypress, tamarack, and dawn redwood
• they all have needles
• and then they drop them

So we have the live-fast-dye-fast deciduous leaves then we have the slow-and-steady conifer needles and then we have something in between. Any guesses on why it’s beneficial to be both needled and deciduous?