I find it remarkable the range of climates apples are grown in. Sure, some thrive in cold climates and are able to withstand frigid winters like Honeycrisp and others do well in the tropics like Dorsett Golden, but some like Wealthy do well in both. Many of the Russian imports to North America in the 1870's such as Red Astrachan and Yellow Transparent do well in "low chill" environments also and can really take the heat. But I find that in keeping with the adaptability apples show in other areas like pruning and rootstocks. Apples are easily trained to just about any shape or size, and will fruit merrily along just about wherever you grow it, from a "stepover" espalier a foot off the ground to a big bushy shade tree. The range of dwarfing rootstocks is also remarkable, more than all other tree fruits combined. Apples are also quite forgiving when trying to graft them, and seem to look for any excuse for the graft to take. I also watch a tree adapt to the climate after it's been planted. When we first plant a Fuji apple, it will keep the leaves until April. Each year it will lose them a little earlier until after about 5 years it drops them by New Years, leaving the still-firm apples hanging another month. That's why we've planted the hundred or so of varieties we have, hoping to draw out some of these qualities that are locked inside the apple. I just wish we had more room to plant a lot of seedlings also, as some apple core tossed aside may contain the genetic traits of the next Wealthy or Dorsett Golden.
Actually they cannot adapt, you are seeing what is already in them when you plant them being expressed.
A good point Ron. Many of us only see a portion of the performance of the apples we grow. Some are better keepers the further north they are grown, while others are sweeter in a hotter climate. Rome Beauty for instance, is considered a mediocre fresh-eating apple and used mostly for pies and cider (although they are good for a week or two off the tree). But when grown in a tropical climate they are especially sweet and flavorful. My point is do not automatically dismiss as unsuitable an apple that does well in a region much different than your own. Anna is considered a very low-chill apple, but many people are surprised to hear that it is grown in Zone 4 in Oxford, New York. Wealthy is grown in the tropics. Some like Gala seem to attain the same size and quality no matter where it's grown. Luther Burbank encourage people in all regions to plant seedling apple trees in order to find varieties that thrive in regions that have not grown apples before. So come on all you cubicle dwellers, plant those seeds!
Interesting observation, Ron. Much will depend on your defination of adaptation. When the settlers moved further South, they brought their apple plants and planted them. These plants underwent acclimatization (meaning as when a plant or organism manages to survive in a new environment}. Acclimatisation is termed as physical adaptation (refer to Wikipedia encyclopeda). In the case of apples cited by applenut, there appears to be behavioural changes as well with regards to sweetness and the year round flowering and fruiting of his trees. This is NOt behavioral adaptations, according to what you claim? I suspect there could also be physiological adaptations as well. Perhaps applenut may be able to quote changes in his trees to support this claim. Thus due to an individual phenotypic elasticity, plants can adaptation to environmental stesses and pressures. OR you could be right too if you mean that that the plant has not adapted from a genetic point of view. Its genetic maps have not changed at all. However the question remains to test out if the newly acquired traits become inheritable to their progeny. If it does could we claim that the genes have been imprinted with new selectives, which finally shows up as phenotypic variations in their offsprings? Another point of interest to note is this. Even if there are genetic changes in the apple trees cited here we cannot tell from observations until we see the changes in the next generation. This position is also true with mutation of gene.
Biological Adaptation: Aptitudes and Acclimatization (PDF; Watts, E.S., F.E. Johnston, and G.W. Lasker. 1975. Biosocial Interrelations in Population Adaptation. The Hague: Mouton Publishers. Pp. 918.) discusses the terminology of adaptation and acclimatization, with the following passage most relevant: The rule of thumb is: adaptation is generational (requires multiple generations). Acclimatization is individual. An individual does not acquire new traits through the course of its life. Trait combinations different from the parent can manifest themselves in offspring, with an increase in the frequency of those traits in the entire population occurring over multiple generations depending on reproductive success.
On this basis, it would be difficult to see if a particular variety such as Fuji would "adapt" over several generations, as any offspring produced from seed would have quite different traits than the parent anyway.
This is brought over from the "Apple Seedling " thread... I find it interesting that most fresh-eating crabapples like Rescue, Whitney, and Chestnut drop their leaves quite early in the season here, a month before most "domesticated" apples do. I 'm hoping this means that they will be well-suited to fruiting in a warm-winter climate. But I cannot automatically say that leaf-drop is indicitive of warm-climate performance, as Pink Lady never does lose it's leaves- the new ones push the old ones out around May, and it still fruits just fine (so much for the dormancy theory). I've tried stripping leaves on one Fuji tree in November while leaving the leaves on the neighboring Fuji until they drop naturally in February, and it did not make a difference in how early they blossomed or the amount of fruit they set.