Host an Event Volunteer Join Tickets

Support the plant database you love!

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
3 ratings

Saturday - May 28, 2011

From: Lake Charles, LA
Region: Southeast
Topic: Invasive Plants
Title: Why is Water Hyacinth an invasive plant and Pickerel Weed isn't in Metarie, LA?
Answered by: Jimmy Mills

QUESTION:

Water Hyacinth. Would you please tell me why the Eichhornia crassipes (non-native) vs. Pickerelweed (native) is invasive vs. non-invasive? What are easy identifiers for these aquatic plants? Thanks and Regards, K

ANSWER:

Water Hyacinth and Pickerel Weed Pontederia cordata (Pickerelweed) are both aquatic plants in the Water Hyacinth Family (Pontederiaceae).  Although both have purple flowers, they are easy to distinguish by the arrangement of the flowers and the shape of the leaves. Click on each of the links below to compare these features.

Pickerel Weed 

  http://www.vplants.org/plants/species/species.jsp?gid=32287

  more images  

Water Hyacinth

   more images 

Pickerel Weed is a native plant and by definition is not considered to be an invasive species , although it is an aggressive grower. The Water Hyacinth, being introduced from Brazil in the 1880’s, is listed as an invasive species and is the more aggressive grower of the two. This can be attributed to the difference in their growth habit. The Pickerel Weed is an immersed plant, growing in shallow water (< 2 ft). It has roots and rhizomes that attach it to the  substrate, and is thus restricted to growth along the edges of ponds, lakes, and streams. The Water Hyacinth, on the other hand, is a floating plant that has spongy parenchyma tissue in the petioles of the leaves that serve as flotation devices, and fine roots that obtain nutrients from the water. With no attachments, it can quickly cover the entire surface of the body of water where it is growing. It also has a high growth rate (studies have shown that populations can double in as little as six days).
      

 

More Invasive Plants Questions

Non-native pothos ivy from Houston
May 30, 2013 - My pothos devils ivy is about 5 years old and grows outside. A couple of years ago its leaves became spectacularly large, like 12" wide and its stalk about 1 - 2" wide. A couple of years ago i gui...
view the full question and answer

How to tell the difference between native and European thistles
April 19, 2011 - How can I tell the difference between invasive (European) thistles and thistles that are native to Texas? And what is the best way to eradicate the invasive varieties?
view the full question and answer

Plant native Lantana urticoides and not non-native
March 09, 2015 - San Antonio Water System does not want to assist invasive plants but we want to encourage Lantana sp but we need to know what Lantana camara hybrids are sterile
view the full question and answer

Is conium maculatum safe for cataracts from Wewoka OK
September 12, 2009 - My doctor has prescribed conium maculatum for my cataract problems. Is this safe to use in the eyes?
view the full question and answer

Non-flowering mimosas in Texas
July 08, 2008 - I have two mimosa trees, about 3 years old. Both were grown from volunteer seedlings. Neither have flowers nor have they produced seed pods. Are they too young or do they need a source of pollenation...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.