En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - What is the pH of Bald Cypress needles?

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
1 rating

Wednesday - February 24, 2010

From: Llano, TX
Region: Southwest
Topic: Trees
Title: What is the pH of Bald Cypress needles?
Answered by: Nan Hampton and Joe Marcus

QUESTION:

What is the pH of Bald Cypress needles?

ANSWER:

Sorry, but, after an extensive search, Mr. Smarty Plants couldn't find a precise answer to your question.  We can tell you that, according to the USDA Plants Database, the pH requirements for its growth are 4.0 minimum and 6.5 maximum and we can point you to the US Forest Service account with a wealth of information about bald cypress.

We do wonder why you asked the question.  Are you considering using Taxodium distichum (bald cypress) needles as mulch for your garden and hoping to lower the pH of your soil to help particular plants? If that's the case then there isn't an easy answer to the exact results.  The overall effect of bald cypress needles on basic soils should be acidifying, but there are many factors that will affect how much the pH could be changed—the amount of needles and how they're used, original soil pH, soil mineral fractions, water quality and its pH, amount of rainfall, soil biota, etc.

There is some experimental evidence about the effect of cypress mulch on soil acidity.  Cypress mulch is the shredded whole tree (including the needles).  A study in Florida by Stephen H. Brown of the Lee County Cooperative Extension Service ("Response of Hibiscus to Organic Mulches", Proc. Fla. State Hort. Soc. 109:30-33. 1996) compared the effects of five organic mulches—needles of Pinus elliottii (slash pine), municipal solid waste (MSW) composed of refuse from professional landscapers and homeowner lawn organic waste, and shredded mulch from three trees—Taxodium distichum (bald cypress) and two trees that are native to Australia, Melaleuca quinquenervia (Melaleuca) and Eucalyptus sp. (no particular species named) on the growth of Chinese hibiscus (Hibiscus rosa-sinenesis).  Interestingly, they found that all applications decreased the pH of the soil (made it more acidic—going from a range of 7.37-7.63 to a range of 6.47-6.8), but the amounts of the decrease were not significantly different for the 5 treatments or the control with no mulch added.  The cypress mulch lowered the pH of the soil from 7.37 to 6.47 in one year.

 

 

More Trees Questions

City tree ordinance information
January 10, 2010 - Dear Mr. Smarty Plants, I am writing to you in regards to city tree ordinances. I am a citizen of Grand Prairie, TX. and although the city is a Tree City, the city does not have a tree ordinance. T...
view the full question and answer

Graywater with soap on trees and shrubs from Austin
June 18, 2012 - I previously asked you about using rinse water from our top loading washer to water trees and flowers. I have two more questions: Can I use the soapy water to water trees and shrubs? Then I get...
view the full question and answer

How far east to avoid Ashe juniper pollen from Austin?
September 04, 2010 - How far East of San Antonio and Austin do I have to go to avoid the pollen of Juniperus Ashei? Is Bastrop county safe? I'd be happy if it were gone 90% of the winter days - will the wind keep it aw...
view the full question and answer

Rock under space for Bigtooth Maple in San Antonio
May 20, 2013 - I just got a 10 gallon Bigtooth Maple in Medina TX for my home outside loop 1604 in San Antonio. I hit rock about 7 inches in when trying to plant it..I am entertaining the idea for a raised bed to le...
view the full question and answer

Feeding live oak and redbud trees from Fredericksburg TX
October 23, 2012 - Can you please tell me what to feed my live oak and texas redbud trees that survived the drought? We have granite soil.
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