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 - January 02, 2007

From: Leander, TX
Region: Southwest
Topic: Propagation
Title: Rhizobium inoculant for Leucaena and othr leguminous tree seedlings
Answered by: Nan Hampton and Joe Marcus

QUESTION:

What sort of Rhizobium inoculant would be appropriate for Leucaena and other leguminous tree seedlings?

ANSWER:

It is correct that legumes such as White Leadtree (Leucaena leucocephala) and, as another example, bluebonnets, require Rhizobium bacteria to enable them to fix atmospheric nitrogen for use by the plant. Furthermore, there are different strains of Rhizobium and the strains that are effective for bluebonnets are not necessarily effective for Leucaena. The Rhizobium strains are species specific. It is possible that the proper strain of Rhizobium is present in your soil already. You can check this by looking at the roots of your Leucaena. If there are nodules present, then it already has the correct Rhizobium species. If you have access to mature Leucaena plants, you can simply harvest some soil from around the roots of them and inoculate your seedlings' soil with some of it. It would only take a very small amount per pot. You could mix a handful or two of native soil into a pile of potting soil and that should do the trick—nothing fancy; the roots and the Rhizobium will find one another.

Research in Australia has cited two strains of Rhizobium that are effective with Luecaena. In acid soils Strain CB3060 (TAL1145) was most effective in N2 fixation. This is cited in Tolerance of Leucaena to Acid Soil Conditions by F.P.C.Blarney and E. M. Hutton, p.84. In the article "Establishment and Early Growth of Leucaena" C. M. Piggin et al., p. 87, report strain CB81 was found reliable and strain NGR8 less reliable. They also report (p. 88) CB3060 (TAL1145) is good in acidic soils as well as more neutral soils.

Unfortunately, there are few sources for obtaining Rhizobium cultures. I did find one source, Becker Underwood in Australia with worldwide production and marketing, for purchase of CB3060. The USDA has a Rhizobium Germplasm Collection that provides free cultures for research but they do not have a database of strains available. You can see a list of other bacterial culture collections worldwide.

For a good discussion of seed treatment and nitrogen fixation see Agroforestry for the Pacific Technologies from the U. S. Forest Service and also Nitrogen Fixing Tree Start-up Guide from Agroforestry.com.

You can also check with the Williamson County Extension Office of the Texas Agricultural Extension Service and see if they know of the availability of Rhizobium strains.

 

More Propagation Questions

Starting wild plant seeds indoors from Dallas TX
February 23, 2014 - Is it possible to start some Phlox drummondii or other native wild flower from seed indoors, and then transplant to my garden? If so, can you suggest some?
view the full question and answer

Native grass for Austin to sow in the early spring
December 02, 2010 - What is the best native grass seed to plant in the Austin area? What is the best time of year to plant? I'll be planting in an area that has no real established grass.
view the full question and answer

Problems with a Hackberry tree in San Antonio.
September 23, 2010 - Our old hackberry tree fell over last year. Now we have dozens of new ones popping up in the same area. We want to transplant a few to another area of the yard, but they aren't surviving. It appears ...
view the full question and answer

How to propagate Clematis texensis in Austin, TX?
May 14, 2012 - How do I propagate a Clematis texensis Buckl. Scarlet leatherflower from the seed pod?
view the full question and answer

Adventitious sprouts on oak tree in Austin
April 26, 2010 - Hello, I have an Oak tree which was planted in about 2002, which has adventitious sprouts. The tree has always sent these up, and we cut them off below ground. The tree has always been a 'runt', b...
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
© 2014 Lady Bird Johnson Wildflower Center