![Orange sulphur butterfly (<i>Colias eurytheme</i>) on common dandelion (<i>Taraxacum officinale</i>) <span class="nonNative">[non-native wildflower]</span>
C&O Canal Nat'l Historical Park - Great Falls, Western Montgomery County, MD](https://photos.smugmug.com/SourceGalleries/2012/03-28-12/i-F68ggtT/0/4662f0fd/L/2012_P1000969-L.jpg)
Orange sulphur butterfly (Colias eurytheme) on common dandelion (Taraxacum officinale) [non-native wildflower] C&O Canal Nat'l Historical Park - Great Falls, Western Montgomery County, MD
all nature photoswildflowerscarderockMontgomery CoMarylandwildflowers of springc and o canal
![Orange sulphur butterfly (<i>Colias eurytheme</i>) on common dandelion (<i>Taraxacum officinale</i>) <span class="nonNative">[non-native wildflower]</span>
C&O Canal Nat'l Historical Park - Great Falls, Western Montgomery County, MD](https://photos.smugmug.com/SourceGalleries/2012/03-28-12/i-F68ggtT/0/4662f0fd/Ti/2012_P1000969-Ti.jpg)
![Toadshade trillium, rare greenish-yellow form (<I>Trillium sessile</I> f. </I>viridiflorum</I>)
C&O Canal Nat'l Historical Park - Carderock Recreation Area, Western Montgomery County, MD
[Note: The bright yellow <I>T. luteum</I> isn't found around here except as garden escapes.]](https://photos.smugmug.com/SourceGalleries/2012/03-28-12/i-g5fpgqm/0/c9737efd/Ti/2012_P1010084-Ti.jpg)
