Comparative picture: Chromolaena odorata & Ageratina adenophora

[Dinesh Valke]

Dear friends,

This post showing comparative pictures of Chromolaena odorata AND Ageratina adenophora.
... hopefully will help to reduce any confusion between them.


Here are some excerpts from earlier post of Gurcharan ji [ https://groups.google.com/d/topic/indiantreepix/jRwrq_wfsFM/discussion ]
... it will further help in distinguishing them.


xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

from Gurcharan ji:

.... leaves (of Ageratina) much larger and broader than Chromolaena odorata. The inflorescence is also much different, an erect spreading panicle in Ageratina.

Ageratina: Phyllaries persistent, 8–30 in 2(–3) series, 0- or 2-nerved, lanceolate to linear, ± equal (herbaceous). Florets 10–60; corollas white or lavender, throats obconic to campanulate (lengths 1.5–2 times diams.); styles: bases sometimes enlarged, glabrous, branches linear, seldom distally dilated.

Chromolaena: Phyllaries usually readily falling (at least in fruit), 18–65+ in 4–6+ series, 3–5-nerved, ovate to oblong or lanceolate, unequal (papery or herbaceous), outer shorter. Florets [6–]15–40[–75]; corollas white or purple to blue, lavender, or reddish, throats cylindric (lengths 3–4 times diams.); styles: bases not enlarged, glabrous, branches linear to linear-clavate.

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

from Vijayasankar ji:

Ageratina adenophora ALWAYS occurs in higher altitudes, whereas, Chromolaena odorata is usually found in plains (may be with some exceptions).
A.a. has purplish stems and petioles, while C.o. is generally green throughout.
A. adenophora can also be distinguished by its leaves which as triangular (deltoid) in outline with a more or less truncate (straight) base (except subcuneate at petiole).

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


Many thanks to Gurcharan ji and Vijayasankar ji for making it easy to sort these two species.


Regards.
Dinesh

[Gurcharan Singh]

Thanks Dinesh ji, great job done.

I would also be uploading my photographs from Delhi of Chromolaena

-- 
Dr. Gurcharan Singh
Retired  Associate Professor
SGTB Khalsa College, University of Delhi, Delhi-110007
Res: 932 Anand Kunj, Vikas Puri, New Delhi-110018.
Phone: 011-25518297  Mob: 9810359089
http://people.du.ac.in/~singhg45/ 

[Gurcharan Singh]

I also notice the stigmas of Chromolaena are much longer than in Ageratina.

-- 
Dr. Gurcharan Singh
Retired  Associate Professor
SGTB Khalsa College, University of Delhi, Delhi-110007
Res: 932 Anand Kunj, Vikas Puri, New Delhi-110018.
Phone: 011-25518297  Mob: 9810359089
http://people.du.ac.in/~singhg45/ 

x