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3. Grannom vs Apple Caddis

While the Grannom Caddis and Apple Caddis are both from the Brachycentrus Genus, they are seperate "species". I believe much confusion is caused by some who refer to both as the "Grannom". Grannom (species: numerosus) is not the same color, nor does it hatch the same as the Apply Caddis (speicies: applachia). Pupa of the Grannom have a dirty olive, to dark olive body, with brown wing pads, and a brown shuck.They often hatch mid morning. The Apple Caddis Pupa is a light brighter olive, and a amber wing pad and amber to ginger shuck. Apple Caddis tend to hatch later in the afternoon. While size might be the same, the coloration of the adults have a completely different look. Apple Caddis adults have a very light colored wing, and a light (apple green body color). Grannom adults have a brownish wing with a body of dark olive, mixed with brown to black coloration. I have further noticed that the Grannom seem to hatch over much of the stream while Apple Caddis seem to hatch closer to shore. I'm just trying to clear up the problem of some calling both the Grannom, which leads to much confusion.

I read this and saved this post from Gonzo on grannoms. I printed it out and keep in the pages of my caddisfly "bible", "Cadddisflies" by gary LaFountaine. Here is a link to Gonzo's post (3rd one down):

http://www.troutnut.com/topic/298

Ooops, link doesn't work. Here's a copy of Gonzo's post:

Grannom, American Grannom, Shadfly, Apple Caddis, Mother's Day Caddis, and Black Caddis are all common names applied to Brachycentrus species. Mother's Day Caddis is the most common Western nickname for Brachycentrus occidentalis, a Western "grannom," but I have also heard this name applied generally to "grannoms" here in the East.

In PA, it is useful to think of "dark grannoms" and "light grannoms." The species your flies are imitating are more typical of the dark grannoms. The "apple caddis" is a light grannom. Most of the important (PA) Brachycentrus species have overlapping hatch periods, so either dark or light imitations (or both) can be called for, depending on the stream.

Here's my current breakdown for important PA species:

Brachycentrus numerosus--Penn's Creek Caddisfly, Dark Grannom, Dark Shadfly; adults have dark-mottled wings and dark blackish green bodies; pupae usually dark with green lateral stripes and dark wingcases.

Brachycentrus lateralis--Striped Grannom, Dark Grannom, Black Caddis; adults have dark wings and pupae are typically dark olive with tan lateral stripes and dark wingcases.

Brachycentrus nigrosoma--Little Dark Grannom, Little Black Caddis; adults/pupae are smaller and darker than numerosus.

Brachycentrus appalachia--Apple Caddis, Light Shadfly, Light Grannom; adults have very light tannish or grayish wings (almost white when freshly emerged) and apple green bodies; pupae are apple green with tan wingcases.

(Brachycentrus solomoni and incanu are also found in PA. B. solomoni is very similar to numerosus, and incanu is rather rare.)

Most "grannom" activity in PA occurs from mid-April to mid-May. During that time, if you carry imitations of dark and light grannoms (adults and pupae) in sizes #14-16, you should have most bases covered.

You are right that the adult imitations are seldom very good during the emergence (pupa or emerger patterns are best). During the egg-laying activity, however, they are often very effective. The fish may prefer skittered, dead-drifted, or wet adult imitations depending upon the concentrations around their lies.

Does anyone have any good Apple Caddis recipes? I want to get ready for spring on the Delaware and have some tying time now.

Louis,

I have both a pupa and adult that work quite well. I'll email you photos and tying recipes - with instructions if any steps are complicated.

Thanks, Matt,

Louis,

Here's a thread from last year you might find interesting to revisit.
http://www.troutnut.com/topic/6591/Brachycentrus-Pupal-Behavior

Here is some great info posted by LLoyd Gonzales aka Gonzo a long while back on Grannoms in the PA and Catskill area:

http://www.troutnut.com/topic/2273/Grannom-vs-Apple-Caddis