Explore Plants

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
    
 

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

Saturday - April 09, 2005

From: Fresno, CA
Region: California
Topic: General Botany
Title: Smarty Plants on spines
Answered by: Nan Hampton

QUESTION:

What do you call part of a plant that is needle-like or has spikes or bristles?

ANSWER:

The sharp projections found on plants, which are used mainly as a defense against animals, have several different names and origins. Botanists identify three major kinds: thorns, spines, and prickles. The thorns are modified stems ending in a short point. They originate from axillary buds at nodes (where leaves or branches arise). Texas hawthorn (Crataegus texana) is an example of a plant with thorns. Spines are modified leaves or parts of leaves. The American holly (Ilex opaca) and agarita (Mahonia trifoliolata) have leaves modified with sharp projections from the edges. Cactus spines are modified sharpened petioles (leaf stalks) without the leaf blades. Prickles are woody outgrowths of the epidermal tissue or bark and occur in irregular patterns between the nodes. Prickles are often recurved and can serve as support for vines as well as a defense mechanism. Prickly ash, or Tickle-tongue (Zanthoxylum hirsutum), in the Family Rutaceae, and raspberries and other members of the rose family (Family Rosaceae) have prickles.

Additionally, many seeds and seed cases have hooks and barbs that enable them to attach to clothing or animal fur and help to disperse the seeds. Two examples are the Canada cockleburr (Xanthium strumarium) and the devil's claw (Proboscidea louisianica).

You can read more about "Prickles, thorns, spines and their relations" on the National Council for the Conservation of Plants and Gardens web page.

 

From the Image Gallery


Texas hawthorn
Crataegus texana

Texas hercules' club
Zanthoxylum hirsutum

Louisiana devil's-claw
Proboscidea louisianica

American holly
Ilex opaca

Texas hercules' club
Zanthoxylum hirsutum

Grayleaf red raspberry
Rubus idaeus ssp. strigosus

More General Botany Questions

Will a Venus flytrap bite?
December 01, 2008 - Will a venus flytrap bite a person? Taylor
view the full question and answer

Cold hardiness zones for plants from Jackson MS
October 02, 2010 - How to search the plant database by cold-hardiness zone? Is it possible to do combination search by zone (not just state?) With the information provided with plant, I do not see the zone listed. Ma...
view the full question and answer

Flower color in shooting stars (Dodecatheon meadia)
February 25, 2010 - Shooting Stars (Dodecatheon meadia) come in the colors white, lavender and purple in the eastern U.S. Is this just genetic variability or does soil chemistry affect the flower color?
view the full question and answer

What caused purple heartwood in my Tuliptree?
June 15, 2009 - My Tulip tree was hit by lightning and all bark from the base of the tree up to 50 feet was blown off. The tree also sustained a significant crack through the trunk. When the tree was cut down, we...
view the full question and answer

Water-saving strategies of drought-tolerant plants
April 04, 2014 - Although "drought tolerant" plants are fairly well documented, it's clear that many different strategies are responsible, such as a huge root system (like Mesquite). I'm interested in learning the...
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.