Select trees from the Smithsonian Gardens Tree Collection are being actively observed to record changes in phenology (seasonal changes). Smithsonian Gardens hopes to engage the public in a citizen science project that contributes observations to the USA-NPN database. Nature’s Notebook is a national, online program that encourages citizens to observe plants and animals in their region and regularly record the cycles of the natural world. This information can be used to make informed land management decisions, aid in scientific research, and influence policy.
Please visit the Nature’s Notebook website to Learn How to Observe. Look for Smithsonian Gardens under Botanical Gardens to add the museum sites to your observation deck. Once you select Smithsonian Gardens as one of your partner groups, you will have the ability to add observational data about the trees listed below.
Asimina triloba • 1 • Custard Apple, Papaw, Pawpaw, Pawpaw apple, Custard Banana, False Banana, Poor Man's Banana, Hoosier Banana, Indiana Banana, Michigan Banana, Nebraska Banana, White Plum
  • Small understory tree reaching ~20ft tall
  • Smooth bark with lenticels
  • Simple leaves, widest above middle
  • 6 maroon petals form cup-like flower
  • Produces fleshy fruit, with edible custard-like flesh
  • Native to Northeast, part of a tropical family
View Nature’s Notebook species profile here
Supplemental information from Nature's NotebookPawPaw Phenology
Cercis canadensis • 2 • Eastern Redbud, Judas Tree
  • Small deciduous tree, ~30ft
  • Understory tree, adaptable to many soil types
  • Heart-shaped leaves comprise the rounded crown
  • Pink pea-like blooms emerge before foliage
  • Flowers are borne directly on trunk and stems
View Nature’s Notebook species profile here
Prunus serrulata 'Kanzan' • 3 • Cultivar of Oriental Cherry, Kanzan Cherry, Kwanzan Cherry
  • Vase-shaped, spreading to 40ft tall and wide
  • Fruitless cherry cultivar
  • Produces double flowers in shades of pink
  • Ovate leaves with serrated edges
  • Leaf color changes from red to green to yellow-orange
  • Sensitive to pollution
Zelkova serrata • 4 • Japanese Zelkova, Sawleaf Zelkova
  • Deciduous tree, reaching ~80ft tall
  • Low maintenance, shade-tree
  • Non-showy flowers
  • Purple-red fall color
  • Alternative street tree to U. americana (see Dutch Elm Disease)
View Nature’s Notebook species profile here
Cercis canadensis 'Hearts of Gold' • 5 • Hearts of Gold Eastern Redbud
  • Naturally occurring cultivar of C. canadensis
  • Differences include
  • Flowers emerge on year old growth, opposed to 2-3 years
  • Rarely produces seed pods
  • Characteristic golden foliage fades to chartreuse
Ulmus americana • 6 • American Elm, White Elm
  • Large, deciduous tree reaching ~80Ft tall
  • Vase shaped, with broad crown; provides great shade
  • Small, green flowers
  • Historic street tree, affected by Dutch Elm disease
  • Green-yellow samaras appear May-June
View Nature’s Notebook species profile here
Magnolia grandiflora • 7 • Southern Magnolia, Bull Bay, Laurel Magnolia
  • Broadleaf evergreen reaching ~80ft tall
  • Dark green, waxy leaves
  • Cream colored flowers with 6 petals, strong fragrance
  • Bright red seeds develop in the fall
  • Brown-grey bark, scales appear with age
View Nature’s Notebook species profile here
Quercus virginiana • 8 • Southern live oak, Virginia live oak, Live oak
  • Long-lived evergreen
  • Tall tree with stout trunk and broad crown
  • Insignificant flowers arranged in catkins
  • Surface scales appear in red-brown furrows on the bark (young)
  • Mature bark darkens and becomes blocky
  • Symbol of the south, common along plantation roads
View Nature’s Notebook species profile here