Opuntia hybrid

This interesting looking Opuntia is a common hybrid found around Fredonia, with one parent been Opuntia phaeacantha. The plants there vary widely in the size of the pads, and spines - from completely naked to very spiny. Some plants have purple pads and some completely green. From the bud it seems like that the flower color is pink.

Opuntia nicholii

This is a large form of O.polyacantha, occurring around Glen Canyon - Marble Canyon area on Colorado River.

Sclerocactus parviflorus

This almost white flower comes from the population where white and pink flowering plants, with spines from brown-red to pure white are growing together.

Sclerocactus whipplei 'rosei'

Sclerocactus whipplei is known to have yellow flowers. This pink-flowering plant makes it very confusing, but if you look closely you see the distinct upward-pointing flat white spine, characteristic to the species. It is well seen on original 1856 illsutration by Paulus Roetter stored in National Museum of Natural History  (click the link to see).
The pictured plant is probably as small as those plants can flower - very encouraging sight for those who grow  them from seed.

Pediocactus peeblesianus

Still usually called by it's original name 'Navajoa' this plant rare both in collection and in nature. The plants are restricted to a very specific habitat and been small are very hard to locate. They are usually grafted in culture, but with better understanding of their requirements more and more people reporting success in growing the plants on own roots.

Escobaria vivipara 'kaibabensis'

Escobaria kaibabensis is a smaller form of E.vivipara, a common species found in Arizona, Utah, Nevada and New Mexico. This species does well in culture, blooming reliably in spring or early summer. The picture is taken on the Eastern slopes of Kaibab Plateau.

Echinocactis polycephalus xeranthemoides

Another species from Navajo Bridge area. These plants are easy to see there, a short walk from the parking. It is also much easier in culture than the more widespread ssp. polycephalus, due to it's habitat been within the summer monsoon zone and longer growth period.