What Is the Average Height for a Birch Tree?

Sweet/ Cherry Birches avg. 12-16 meters River Birches avg. 12-22 meters Paper Birches avg. 15-22 meters Your tree has a lot of growing left regardless of which one it is!

1. A non-technical account of the Birch—Swinnerton-Dyer Conjecture

Moreover, there is not yet a good conceptual framework in which to view the problem, which perhaps explains the lack of non-technical or popular literature on the subject. If you are looking to learn about BS-D in a more serious way, or would like a nice (historical) overview, you might enjoy the paper of John Tate, "The Arithmetic of Elliptic Curves", Inventiones 23 (1974)

2. Are these birch or aspen trees?

I think they are birch trees (Betula), based on the white bark with black horizontal patterns (Lenticels). The bark patterns at the base of the trees are also very similar to birch. Either way (relating to one of the comments), it's an autumn picture, where both birch and aspen have yellow leafs (aspen leaves can also be red or reddish, especially at the end of branches). This page also agrees with me (which does not necessarily have to mean that much though), which labels the exact same picture as "birch-tree-wallpaper-3.jpg".I am not sure about the exact species, but I know that there are North American species where the bark can shift between white, pink or reddish. One possibe suggestion/pure guess is Betula neoalaskana, but as you can see from the wikipedia page this species can also hybridize with Betula pendula and other species. To me, it does not look exactly like the Eurasian Betula pendula or Betula pubescens, which I am most familiar with (those are the two species found in Sweden)

3. Are there any preservations on cutting down Silver Birch Trees?

Are Silver Birch Trees Protected

4. Birch reduction of anisole

Chemistry is an experimental science supported by computational methods. Qualitative explanations for reaction mechanisms follow as a result. More on that issue later.The mechanism of the Birch reduction has been investigated by Zimmerman and Wang.1 What are the experimental results? The Birch reduction is first order in substrate, electrons and alcohol. Therefore, the rate-limiting step is the protonation of the radical anion 2 of anisole 1. Based on the observation that the dianion of anthracene is more basic than its radical anion, 2 the authors designed an experiment utilizing 2% d1-t-BuOH as the alcohol source. The argument is that the radical anion, which is less basic than the anion, will be more discriminating,3 favoring protonation rather than deuteration (isotope effect). The more basic anion, 4 or 7, which is less discriminating, will give rise to a higher D/H ratio. Employing deuterium NMR, the meta position in 8 was found to have 7-times the amount of deuterium than the ortho-position. Thus, the ortho-position (2a --> 3) is protonated first; mechanism O (ortho) predominates over mechanism M (meta). --continued-- Calculations showed that the methoxy ortho-substituted cyclopentadienyl radical is more stable than the meta- and para-isomers (red box). But your request was for a qualitative rationale for preferring radical 3 over 6. Radical 3 has an advantage over radical 6 because radical 3 may be written with the radical on the ipso-carbon, the same radical that would be expected to be generated by auto-oxidation of 5-methoxycyclohexa-1,3-diene. Cross-conjugated radical 6 does not have this option.1) H. E. Zimmerman and P. A. Wang, J. Am. Chem. Soc., 1993, 115, 2205.; H. E. Zimmerman, Acc. Chem. Res., 2012, 45, 164. 2) V. D. Parker, M. Tilset and O. Hammerich, J. Am. Chem. Soc., 1987, 109, 7905. 3) Consider by analogy that chlorine atoms are less selective than bromine atoms in the radical halogenation of alkanes.

5. Why Birch St. and Higgins Dr.?

These are simply the streets near her childhood home. It's part of her PTSD therapy. She's supposed to repeat these names whever she starts to lose herself. This is to remind her that she's the person who grew up in that house.

6. How do Birch, Maple and Ash baseball bats compare in terms of hitting performance?

There are several differences in the properties of the three kinds of wood. I can discuss how these properties translate to hitting performance. For the sake of simplicity, I am just going to compare maple and ash. The properties of birch are somewhere in between maple and ash, but it is closer to maple. You can think of birch as a maple bat that has some of the benefits of ash.Density: Maple is the heaviest of the three and ash is the lightest. This means that maple provides the highest rebound velocity. So if you hit it on the sweet spot, you should be able to hit the ball further. However, higher density means that maples bats are heavier compared to ash, so you can create higher swing speed with ash. To compensate for the weight, all maple bats have cupped ends to remove some weight. While most are OK with it, some hitters who are used to uncupped bats will feel that maples are not balanced. Also, even with a cupped end, maple will feel heavier. Maple bats produce a higher pitch "pop" that a lot of hitters like instead of "crack" that ash produces. I know that sound should not be a factor in performance, but humans are sensory creatures, and we will subconsciously equate a pleasant sound with performance.Sweet Spot: Ash has the largest sweet spot. Flex: Due to density, ash flexes more. Some feel that this flex actually helps to create a trampoline-like effect, driving the ball farther, compensating some of the distance lost due to lack of rebound velocity. However, since maple bats don't flex as much, the manufacturer can put on harder lacquer on the surface to give them even more pop.Graininess. Ash bats are very grainy. Highly skilled players are very particular about how densely the grains are aligned and shaped. A company like Hillerich and Bradsby sends its major league clients a dozen or more bats at a time, and only a few get used in games. Also, as taught in little league, you have to swing ash bats with logo up or logo down to reduce the chance of breaking. With maple bats, grains are small and not even visible. While major leaguers are still picky about their maple bats, more of them get to be game bats. There has been a critical shortage of ash woods that are baseball bat quality. Therefore, if you are buying an ash bat off of a shelf at a good sporting store, you may end up with a low-quality wood. You have to know what to look for and inspect carefully before buying. With maple, there is a better consistency even with amateur level bats.Durability: Maples are maligned by baseball fans because when it breaks, it shatters, creating sharp chunks of wood and shrapnel flying everywhere. Ash bats break along the grain, and they are more likely to splint, rather than break off. Overall, both bats break at around the same frequency. Ash bats tend to break on inside pitches (jammed) while maples tend to break on outside pitches (cued). So depending on your hitting tendencies, you can reduce the number of bats used in a season merely by selecting the right type of bats.Cost: Maples are about twice as expensive. When my son played, I bought him a composite bat which lasts forever and approved for most amateur leagues. How do Birch, Maple and Ash baseball bats compare in terms of hitting performance?