The Great Fall Monarch Migration


There is something amazing happening in the North Texas area right now:  The annual fall monarch butterfly migration into Mexico.

Last weekend, I saw multitudes of monarchs making a pit stop at my home, which is about 3 miles east of Interstate 35 in Carrollton, Texas.  The butterflies were partaking of our vitex tree which still has some sparse blooms left over from summer.

As such, today I’d like to share a couple of personal photos and just a few tidbits of information I find fascinating about this migratory event and will leave the in-depth information to the website above and others listed within this post.

  • Monarchs are the only butterflies known to make up to a 3000 mile, two-way migration.
  • All monarchs east of the Rockies will funnel through the state of Texas to their destination in central Mexico. A smaller number west of the Rockies will overwinter in coastal and southern California.
Monarch on Vitex, Carrollton, Texas, Oct 2015

Monarch on Vitex, Carrollton, Texas, Oct 2015

  • Monarch larvae (caterpillars) feed exclusively on the milkweed plant, which is toxic to most insects and animals.
  • The toxicity of the milkweed stays within the monarch larvae and adult butterflies – making both phases of the insect unpalatable to most of their predators.
  • As I learned a long time ago in my elementary school science class, the viceroy butterfly is a great monarch mimic, taking advantage of fooling predators who may believe they are bad-tasting monarchs!
  • The slight differences between a monarch and viceroy:
    • There is a horizontal black line across the hind wing of the viceroy which is not present in the monarch,
    • there are no dots on the back of the body of the viceroy, and,
    • the viceroy is generally a little smaller than the monarch.


  • It is thought the number of monarchs is declining due to the limited availability of milkweed host plants subsequent to overuse of weed herbicides and sprawling urban development.
  • An effort is underway to re-establish native milkweed plants through federal, state and municipal roadside plantings and by encouraging citizens living along the monarch migratory path to integrate native milkweed into their landscapes. See
  • Milkweed is actually a somewhat attractive “weed” that tends to bloom longer and under circumstances when other plants may not (drought, poor soil). In addition to the species pictured below, there are also pink and bright white blooming varieties.   Another bonus to milkweed is it is a perennial so after it is established you shouldn’t have to re-plant.  If you decide to plant milkweed in your landscape or garden it is important you find seed or seedlings native to your specific area of the US, as some non-native species are actually thought to be detrimental to the monarch and its migration. See
Asclepia Viridis, Green Milkweed or Green Antelopehorn Milkweed Photo courtesy Ladybird Johnson Wildflower Center

Asclepia Viridis, Green Milkweed or Green Antelopehorn Milkweed Photo courtesy Ladybird Johnson Wildflower Center

In conclusion, although rain is forecasted this weekend in North Texas, I hope you find a chance to sit outdoors within the next few days and observe the monarch migration traveling through our area this month.  You may be surprised at just how many of these delicate, but resilient, flying jewels you will see!

Until next time,


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