Hermaphrodite Conifer Cones at Arnold Arboretum — Are Not to Be Missed

Botany rule # 17: all conifer cones, for the last 300 million years (give or take) are unisexual. Each cone either produces pollen (male function through sperm) or seeds (female function through eggs). For well over a century, plant morphologists (members of a rarified discipline that focuses on the principles of plant form and was inaugurated by none other than Johann Wolfgang von Goethe) have known of conifer tree weirdos that can produce strange looking bisexual or hermaphrodite cones in addition to normal pollen-producing cones and seed-producing cones. While no one knows why this happens, it is rare and definitely something to see when the opportunity arises. [Week of April 29] at the Arboretum, one of our Lijiang spruces, Picea likiangensis (243-92*C) has broken bud, revealing hundreds of hermaphrodite cones right at eye level – and easily found at the south end of Conifer Path near Walter Street Gate.


Ice Flowers at the Arnold Arboretum

“Ice flowers?” Never heard of them. That is, until last Tuesday, when the buzz at the Arboretum was all about the ice flowers on Isodon henryi (593-2010*A; 鄂西香茶菜), a Chinese perennial herbaceous plant in the mint family. Needless to say, I was there first thing the next morning! And this is what I saw. Word on the street is that you need air temperatures below freezing and soil temperatures above freezing.


Arnold Arboretum Celebrates Plant Graduation Class of 2021

Plant graduation season, an annual rite of passage at the Arnold Arboretum of Harvard University, is an occasion for pomp and circumstance as well as a reminder of our connections to nature and the power of plants. The Plant Graduation Class of 2021 took place on April 2 and featured more than 500 plants, some rare and endangered, graduating from the nursery and finding placement throughout the 281-acre landscape of the free and open museum teaching the world about plants. Before the plants officially graduated from the greenhouses for their new “careers” out in the field, a commencement ceremony was held to honor the budding and burgeoning Class of 2021. “The fact that there are more and more plants being planted and groomed and protected and nourished shows the importance of this place," said District 6 City Councilor Matt O'Malley. “At the Arnold Arboretum we do conservation, education, and we are trying to make sure people understand their responsibilities to the planet and to their fellow species,” added Ned Friedman, Director of the Arnold Arboretum.


Learn About Pecan’s Intersection of Biodiversity & Human Diversity From Arboretum’s Director Series

The Arnold Arboretum is exploring the meaning, history, and cultural entwines of the pecan in a three-part series. The Arboretum's 2021 Director's Lecture Series Pecan: The Intersection of Biodiversity and Human Diversity will run for free for three consecutive Mondays starting Feb. 22. The pecan tree is native to a region stretching from central Texas to western Alabama, and from the Gulf of Mexico to southern Illinois. Most pecans grown for commercial consumption come from New Mexico and Georgia, which are places with no native pecans, according to the Arboretum.


Astonishing Bark! Arnold Arboretum Director: ‘Once You See This Tree, You Can’t Look Away’

Every once in a while, a tree I often pass catches me off guard and astonishes me. Such was the case with a Korean stewartia (노각나무) near Centre Street Gate. Never have I seen such striking winter bark at the Arnold Arboretum (and I have seen a lot of striking bark). Once you see this tree, you can’t look away. The typical (and always beautiful) large puzzle pieces of bark of varying ages and patinas in beige, dark green, and grey are there.