En EspaŅol

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
Not Yet Rated

Tuesday - April 12, 2005

From: Pittsburgh, PA
Region: Mid-Atlantic
Topic: Plant Identification
Title: Differentiating between Spiraea betulifolia and Spiraea japonica
Answered by: Joe Marcus

QUESTION:

How can I tell the difference between Spiraea betulifolia var. corymbosa (an imperiled species) and Spiraea japonica (an invasive species) in the wild? They both seem to be the same size, color, habit, etc.

ANSWER:

There are a couple ways to distinguish Spiraea betulifolia var. corymbosa from Spiraea japonica. Unfortunately, there are also some pitfalls in these distinctions! In general, our native spirea is white-flowering (occasionally lightly blushed pink), while S. japonica is typically pink to rose-red flowered. The exceptions are uncommon, but can make positive identification difficult. The leaves of S. betulifolia var. corymbosa are broadly ovate to oblong or obovate, between 4 and 7 cm long and usually less than twice as long as wide. If you are not familiar with botanical terminology think, "arrowhead shaped". Spiraea japonica leaves are lanceolate or lance-ovate, between 8 and 15 cm long and 2.5 to 5 cm wide, or typically more than twice as long as wide. Think, "spearpoint or lancehead shaped". Further, the toothed edge of Spiraea betulifolia var. corymbosa usually extends only from the leaf tip to 1/2 to 2/3 of the length of the leaf toward the base, while the toothed edge of S. japonica leaves typically extend nearly to their base. Spiraea japonica escapes from cultivation and can often be found growing in the wild. To further complicate matters, the many cultivars of S. japonica can confuse identification.
 

More Plant Identification Questions

Identification of a shrub in San Marcos, TX
May 20, 2013 - On a walk in Austin's Barton Creek greenbelt, a Treefolks volunteer identified a shrub that I also have on my property in San Marcos as blue candalia. However I can't find a plant by that name via w...
view the full question and answer

Plant identification
August 13, 2008 - Bought a plant don't know what it is or how to care for it. It looks like it's dying. Description: light to dark green, long, skinny, rounded trunk, surrounded and topped with grass like blades(top ...
view the full question and answer

Plant identification of tree in North Carolina
September 07, 2011 - I live in North Carolina have found a tree on our property that has thorny branches and round fruit (perfectly round) with a fuzzy outer layer that starts out green but then turns yellow. The inside r...
view the full question and answer

Plant identification
September 24, 2008 - I found a flower about 5 inches tall and it is Pinkish White the head of it hangs down and looks like a rose that hasn't bloomed yet. It reminds me of an Orchid like Fairy . Its Mystic like! what is ...
view the full question and answer

Plant identification
July 31, 2010 - I have this shrub looking type plant with leaves that smell like lemons. The plant has a very small white flower on it. This shrub shows up in my yard every year in the summer. We are curious as to we...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP | STAFF
© 2015 Lady Bird Johnson Wildflower Center