Two good ways to tell:

1. Grasp a shoot. Do you yell with pain (pungens), or not (engelmannii)?

2. Look at a shoot close-up with a hand lens. Is it hairy (engelmannii), or hairless (pungens)?

Resin

Well Sam, what's the result of this?

Looks to me like 'Hoodie'.

'Hoodie' is one of the nastiest/sharpest engelmanii cultivars I've encountered. Look for the hairs, Sam.

Dax

So you wouldn't want to "Hug a Hoodie"? ;-)

(UK readers will know what this is about!, US readers, google the phrase)

"RESPECT" - Ali G

Here is a link that might be useful: Ali G & Tony Benn *Respect*

Doesn't look good for engelmannii, gentlemen..
The needles were fairly sharp, and the pictures below reveal a fairly glabrous stem..
Let me know what you think, please!

-Sam

Looks like pungens indeed.
Maybe it lost it's wild hairs :0)

A cone of it makes it more clear...

Looks like it could be pungens.

Pungens (smooth)

Engelmannii (hairs)

Does your mag. glass have enough power? I used a jewler's loupe (not knowing the power) and I couldn't make out what Sluice is showing on several of my P. e cultivars.

When you posted this I wondered the same of 'Hoodie' in general. I'll have to check out mine next year.