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?


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
2 ratings

Wednesday - March 04, 2009

From: Goodrich, TX
Region: Southwest
Topic: Wildlife Gardens, Trees
Title: Fertilizing oaks to produce more acorns
Answered by: Nan Hampton


What type of fertilizer would I use on oak trees to possibly increase growth and acorn production ? I have some flooded oak timber that is home to migrating ducks but there is little for them to eat.


There is a great deal of controversy about whether fertilizing oak trees influences their ability to produce more acorns.  Indeed, there are some sources (e.g., Whitetail Stewards Inc.) that say not to waste your time and money fertilizing oaks since there are so many factors that can affect the amount of oak mast produced in any year—rainfall, genetics, general humidity, timing of late frosts, pest infestations, etc.  Additionally, the production of large crops of acorns tends to be cyclic.   Producing a heavy crop of acorns one year usually results in several years with a lower production.  For red oaks this can be a 5-7 year cycle and for white oaks it may be a 3-5 year cycle.  For a thorough discussion of the unpredictability of acorn crops see Improving acorn production - Part I: Factors affecting acorn production of oaks from Whitetail Stewards, Inc. 

Most professionals seem to agree on at least one strategy for improving the amount of oak mast—that is to insure that the oaks that appear to be the best producers are not crowded.  Trees around these high yield trees may need to be thinned so that they are not competing for sunlight and water.  Outdoor Life has an informative article, Mast Production--In a Nutshell, that gives a short lesson in oak biology and how to manage them. The U.S. Forest Service North Central Forest Experiment Station has recommendations on How to Manage Oak Forests for Acorn Production.

If you still think you would like to fertilize your oaks, it certainly is not likely to harm them.  What kind of fertilizer should you use?  You can see in the answer to a previous question about fertilizing oaks, that recommendations from professional landscapers varies.  Some say use a 'standard' fertilizer, while others recommend a 8-2-4 compost-based or a 5-10-5 mixture.  (The numbers refer to percentages of nitrogen, phosporus, and potassium.)

In your flooded oak timber you could add other plants that could provide additional food for your migrating ducks.  Here are some wetland plants that are used by ducks and other waterfowl for food and cover:


Eleocharis montevidensis (sand spikerush)Scirpus cyperinus (woolgrass), Schoenoplectus robustus (sturdy bulrush)

Other aquatic or wetland plants

Duckweeds such as Lemna minor (common duckweed), Potamogeton nodosus (longleaf pondweed), Sagittaria graminea (grassy arrowhead), Pontederia cordata (pickerelweed)

You can find others in "Aquatic and Wetland Plants of the Western Gulf Coast" by Charles D. Stutzenbaker.


From the Image Gallery

Sand spikerush
Eleocharis montevidensis

Scirpus cyperinus

Sturdy bulrush
Schoenoplectus robustus

Knotty pondweed
Potamogeton nodosus

Grassy arrowhead
Sagittaria graminea

Pontederia cordata

More Trees Questions

Tiny holes oozing sap from Austin
August 22, 2012 - My ash tree becomes loaded with butterflies on the trunk. At closer inspection, I see they are drinking sap which is coming from small holes in the trunk. Are the butterflies creating the holes? I ...
view the full question and answer

Are poplar trees and willows safe for animals to eat
August 04, 2008 - poplar trees and willows, are they friendly for farm animals to consume leaves?
view the full question and answer

Replacement trees for southwest facing backyard in Austin, TX.
September 23, 2010 - The back of the house we are purchasing faces southwest and is completely devoid of large shade trees. I have been told that the previously existing trees were destroyed by oak wilt. I am in love wi...
view the full question and answer

Smoketree not flowering in Beverly Hills CA
June 29, 2011 - Why is my Smoke tree not flowering? It is big and the leaves are beautiful but no blooms.
view the full question and answer

Viability of Juniperus ashei for making furniture
June 18, 2007 - My husband uses juniper from Oregon to make beautiful furniture. Underneath the ugly bark is a wonderful wood. Is this the same Juniper as we saw all around Austin, Texas.
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center