Breaking Buds, Already?

Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)


Earlier today, while collecting samples in the Explorer’s Garden area of the Arboretum, I came across a surprising sight. Apparently unaware of Punxsutawney Phil’s recent prediction, this Narrowleaf Standish Honeysuckle (Lonicera standishii forma lancifolia) has begun breaking its winter dormancy. Covered in expanding buds and unfurling, tender foliage, this shrub appears to have jumped forward to an early spring.


Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)


These swelling buds, with their purple and green hues, are a beautiful but untimely sight.  Honeysuckles are among the earliest woody plants to respond to rising spring temperatures and extended day length, typically sporting juvenile leaves in late February/early March. Early leaf-out timing may give a plant a competitive edge–an especially important adaptation for shrubs that receive very little light in the understory.


Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)


This shrub, probably responding to extended stretches of warm weather and bright sunlight, has unwittingly exposed its vulnerable tissues in the dead of winter.  These young tissues are particularly susceptible to freezing temperatures. Once expanded, they will likely be killed off by frosts before winter’s end. Luckily, this plant looks robust enough to survive the loss of a few photosynthetic assets.


Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)


Interestingly enough, this species, a native of China, is semi-evergreen in our climate, and has retained many of its mature lower leaves. In late winter, pairs of brilliantly white, fragrant flowers will emerge. For now, we’ll have to wistfully enjoy these precocious buds as early signs of spring.


Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)

Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)

Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)

Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)

Lonicera standishii forma lancifolia (Narrowleaf Standish Honeysuckle)

Marcescent petioles on Carya laciniosa (Shellbark Hickory)

Carya laciniosa (Shellbark Hickory)


Last week, while photographing dormant buds, I noticed some eerie, finger-like protrusions on the terminal branch ends of a shellbark hickory, seen in the image above. These spent parts are actually the petioles of last season’s foliage. For some reason, these petioles remain on stems through autumn and into winter, long after leaves have changed color and fallen.


Carya laciniosa (Shellbark Hickory)


Marcescence is the retention of dead plant parts that are typically shed during the season. It is commonly observed in Fagaceae, especially among oaks and beeches, which sometimes hold on to spent leaves throughout winter. These leaves are finally abscised in spring, as new foliage begins to appear. In the image below, you can see the base of a petiole splitting from the stem. A leaf scar will remain, showing the vascular connections between the leaf and stem.


Carya laciniosa (Shellbark Hickory)


So why does the shellbark hickory retain its petioles? Some have hypothesized that trees hold on to spent leaves in order to protect tender buds and twigs from hungry herbivores during the winter. It’s possibly that the hickory bears its left-over anatomy as a protective measure against animals that might seek out the precious buds hidden among this spiky armor. Either way, these curved petioles have an ominous presence in the stark winter landscape.


Carya laciniosa (Shellbark Hickory)

Acer rubrum (Red Maple) #2

Family: Sapindaceae

Provenance: Volunteer seedling transplanted from Burlington back yard.

Date Acquired: 8/2013

Approx. Age at Acquisition: 1-2 years old

Notes:

-8/2013, Tree transplanted and planted over rock; roots wrapped in plastic wrap.

-3/2016, Tree dug up and roots examined. Large tap roots wrapped over rock but without much additional branching. Roots rewrapped and soil placed near upper roots to encourage new rooting. Replanted in same spot.


To do: Tree must be allowed to thicken further for one or two seasons.

Acer rubrum (Red Maple)

Family: Sapindaceae

Provenance: Volunteer seedling transplanted from Burlington back yard.

Date Acquired: 8/2013

Approx. Age at Acquisition: 1-2 years old

Notes:

-8/2013, Tree transplanted and planted over tile in backyard in Burlington, MA and allowed to thicken.

-11/2016, Tree healthy but not much larger

-Spring 2017, Tree killed for unknown reason