How can I tell the difference between a primocane and floricane leaf or cane?

So this time of year there is a lot of new growth in the blackberry field. Both floricanes and primocanes are present and providing the plant the food via photosynthesis that occurs in the leaves.  This food (carbohydrates) help to ripen the fruit.

Most of the floricanes are loaded with green fruit by late May, and look like this image below. shorter laterals, short internodes relatively small leaves with 3 leaflets. FYI, caneberries have compound leaves, meaning each leaf has more than one section or leaflet.

Picture 1. Floricane with fruit.

The primocanes usually have thicker stems, that gradually taper at the tips,  and long internodes (area on stem between each leaf). They look like this:

Picture 2. Primocane Note that each leaf has 5 leaflets.

Then there are these canes, at first they look like a primocane, but then with closer inspection, they have little flower buds and only 3 leaflets per leaf.

Picture 3. This is a floricane, note the leaf is comprised of 3 leaflets.

So, there are two types of floricanes, the ones that produce the majority of the fruit on the canes that developed last year. Then there are basal buds that are much more vigorous (and look like primocanes) and produce fruit later in the season (Navaho is probably the variety where we see if most often). Here is a picture of the basal floricane and the primocane. Note that not only does the floricane have fruit, it has 3 leaflets per leaf. Most blackberries and raspberry floricanes have 3 leaflets and primocanes with 5 leaflets.

Picture 4. Floricane with 3 leaflets/leaf  and small flower buds on left, primocane with 5 leaflets/leaf on right.

So, when you are wandering through your fields, take a look, can you tell the difference?

Blackberry plants recovering after the freeze 2007

Image 1. This is a secondary bud that has emerged (semi vertical green stem). There is a remnant of primary stem, it is the brown nub on the right. 

Image 2. Regrowth of laterals after complete loss of primary buds in 2007. 

Reports are in, there was damage, laterals were wilting in the afternoon at some locations after the  freeze this morning and at other farms there was just bud damage (4/12/12).

Above are some images of the plants a couple weeks after the freeze in 2007. These were in a field  of Arapaho. The remnants of the primocane leaves are on most nodes, it is the brown nub on the right side of the node (Image 1).  A few days after the freeze I was in this field and noted 99% blossom kill and most of the fruiting laterals tissue appeared dead (wilted). I did not look for secondary buds at that time. However, about 2 weeks later, secondary buds were emerging, and I could not find the dead primaries (Image 1).