What would the blast pattern be like? At ground zero? as you move further away from ground zero? From an birdseye view.

If you have a good web site that would help that would be great.

The blast pattern is going to be fairly simple in any case, all the trees that aren't completely uprooted or disintegrated are going to be knocked down directly away from the blast. The radius of noticable blast damage will vary considerably depending on a number of factors, but for about a mile diameter you would expect to see nearly all the trees uniformly knocked down (assuming a 20Kt airburst like Hiroshima) and after that see the trees only leaning for the most part (remember that the area is likely to be engulfed in a firestorm prior to a birds being able to view it from the air safely, and there may be little left of the trees themselves in that case). A firestorm is likely in dry, clear conditions, but far less likely during inclement (interesting term, that) weather and very unlikely if the forested area is a wetland.

I did a quick Google search, and http://www.tinyvital.com/Misc/nukes.htm had some useful information on blast damage (meaning that the figures were not badly flawed, as on many sites). Unfortunatly most information available online is obvious propaganda, for the most part wildly exaggerating the amount of damage that nuclear weapons can cause (although there are some that minimize the dangers unrealistically).

One thing that you might notice (assuming that there is not a firestorm) is that animals will have survived even inside the area where trees have been knocked down by the blast. There are several reasons for this, but you are quite likely to notice it if you pass over the area a couple of hours after the blast (again, assuming that the area is not engulfed in flames). This can be surprising, but it is to be expected. Assuming that humans are in the blast area, they too will have some likelyhood of survival depending on distance from ground zero and other factors. However, no animals, including unprotected humans (note that fully protected humans can survive very close to the blast center of an airburst, and just outside the actual crater of a groundburst, and may still be capable of resistance), will survive closer than about 200-300 meters to the blast center, and trees will be stripped of limbs and foliage.

Remember also that even a 20kt fission blast like Hiroshima would make a bright flash. Animals and humans could be blinded, depending on the direction they were looking at that instant. The shock wave could throw heavy objects long distances. Deafness would sometimes occur. Exposed humans could get various cancers, especially lieukemia. The ground water has been exposed to radiation, I imagine the level of contamination would depend on the type of rocks in the area.

You might extrapolate some interesting long-term effects. Would the forest recover from this fire like any other fire? What if there was a subtle difference? Perhaps earthworms or bacteria could not live in the soil. Or maybe the ground was very rocky before, but the nuke left pulverized layers of dust and ash that eventually become very hospitable to plants.

It's an alternate history, so a bit twisted. But then so am I, lol.

A better (interesting use of the term) method of destroying a large forest would be to firebomb it in a radial pattern, with a large concentration of incendiaries at the center. This would lead to a classic firestorm, limited in size only by how far you extend the radius of the bombing. A firestorm is best at destroying areas larger than a mile in radius, and because the underlying principles are the same as a major weather system, it is actually more effective the larger an area you use, so it is possible to destroy an area of over 100 miles radius with less than a tenth the cost of a single nuclear weapon (compare this with the 1/2 mile radius of complete destruction wrought by a 20 Kt bomb).

For such a large fire, particularly arranged into a coherent cyclonic firestorm, the long term damage to the environment would be even greater than that experienced 1/2 mile from ground zero of a 20 Kt airburst. The fire would remove all oxygen from the environment, and the soil would be baked over a period of hours or days (depending on the size of the firestorm), altering its chemical composition (particularly the presence of nitrates, which confer soil fertility). While there would be no residual radiation, that is less of a danger for nuclear weapons than is generally supposed (many humans irrationally fear radiation, for some reason). And the extreme conditions would produce chemical contaminations that would be much more harmful in both the short and long term. The complete removal of all ground cover would mean that rainfall would only damage the environment further, and water seeping into the soil would pick up higher concentrations of metals and salts before reaching the water table. The water table itself would probably be dramatically lower in many areas.

Only aggressive irrigation, fertilization, and cultivation would return the land to productivity, and it would take decades at least (and might fail, at that--environmental and agricultural science in the fifties would not have been up to the task).

1) Fallout. An nuclear airburst will level a larger area, but will produce negligable fallout, whereas a gound burst will level a smaller area, but produce much fallout, requiring everyone downwind be evacuated.

2) If you want to jack up peoples' USE of a forest, while leaving the trees, use persistant nerve agents. Any animal entering the area will die a horrible, if quick, death. This should not pose a problem to your 1950's setting, as Hitler actually had these chemicals in the 1940's. (They were an accidental by-product of Germany's pesticide/agriculture industry! It is speculated Hitler didn't emply them because he thought -- mistakenly -- that the Allies had them, too.)

I started this novel, a second in a series of stand alones, about 6 days ago. It is now 20,000 words long. Forst draft, in need of much fill in and tweeking. I do very little description in first drafts, and I have made a note to fill in the details of the forests demise.

This helps a lot. Thanks---medical stuff I can tell you, I only have surface knowledge of chemical and nuke warfare.

The fire you describe would do more damage than a 20kt nuke.

However, the nuke would start a fire, too. And 50s era firefighters might not be too keen on charging into a fallout zone. The fire might rage for days before they start fighting it.

Also, the lingering radioactivity would do more to desecrate the forest than merely burning it.

(edit: spelling)

As for fighting a firestorm, once the weather pattern is activated, it really is beyond human capability to "fight" it, the updraft at the center creates high winds circling in from the surrounding area, which both oxygenate and spread the outlying fires. And in the 50's, little was known about gamma and neutron radiation, the primary components of "fallout" radiation. Soldiers were commonly sent on exercises into nuclear test sites on the theory that only the initial radiation was dangerous.

Any large forest can absorb a significant amount of radioactive material without being "desecrated" or significantly harmed. A forest of a few hundred square miles could absorb all the radioactive material from a 20 Kt blast without much difficulty (the actual blast damage would take longer to heal).

Tunguska levelled something like tens of thousands of acres. Nobody would object if, in a late-1950's setting, she used a 10-20 MT airburst -- like Tunguska.

As for Cherynobyl, that released a LOT more radiation than a bomb ever would.

Unless you but a cobalt jacket around the bomb. THAT would contaminate -- desecrate -- the landscape for 1,000-10,000 years.

All of these suggestions would cause the desired damage. The important questions revolve around the culture of the forest lovers. Would they have an irrational fear (or total lack of fear) for the minor fallout caused by an air burst? Or would they sacrifice themselves by the thousands to fight the enormous firestorm described by Survivor? In their minds, would a very small amount of contamination constitute desecration?

You can build tension by giving the attackers a good feeling for what would hurt them the most. You can build even more tension (and make the story more realistic) by having the forest-lovers realize their weaknesses and take precautions. For example, if you decide that Survivor's firestorm attack would be the worst possible thing that could happen to the forest, then the forest-lovers ought to have plans and equipment to prevent such a firestorm. Perhaps the Sacred Forest is a "no fly zone" and any aircraft or missile that comes within 50 miles is automatically shot down. Or maybe the forest-lovers realize exactly where incendiaries must be detonated to create the coherent cyclonic firestorm, and have already built (or started to build) a network of artificial lakes and canals laid out to make a coherent firestorm impossible. Or they realize that they are vulnerable to a nuclear attack, so they create a doctrine that says True Believers in the Sacred Forest are immune to radiation . . .

No matter what the forest-lovers do, your attackers must be clever. If there is an anti-aircraft system they will thwart it. If there is a canal system they will sabotage it. If there is a belief system they will use a different type of attack that the forest-lovers are not expecting (like Chad's nerve gas).

After the bomb is dropped on Japan, these people come out of their shell and decide they must interact with the world because of this great danger to nature. And it goes from there. A lot of this is back-story, the reason for the attacks. The story starts after the attacks, but the reasons ect will be woven in as I go along.

I am going to use a combination of things, they do have good fire fighting capabilities, and good forest management. They were not prepared for a nuclear attack, or for the nerve gas attack, which was used to destroy their livestock and most of their people.

Thank you so much, the ideas are great.

Chad's notion of using nerve gas (or a more persistent liquid or powdered agent) would be almost ideal, though, particularly for attacking a human population that actually lives in the forest. It would contaminate everything, air, water, food, and cause horrible effects even short of lethality.

THE EFFECTS OF NUCLEAR WEAPONS 3rd ed., eds. S Glassman and PJ Dolan, United States Department of Defense and Energy Research & Development Administration, 1977, chap. 12.

Various comments about the effects of radiation on plants. These will only be most relevent in a fallout situation, although we could extrapolate them to the plants near ground-zero exposed to the blast radiation.

Random facts:

Seedlings collect more radiation than plants near harvesting. Thus, mature crops could probably still be eaten if they are washed throughly.

The effects you expect: lower growth yield, deformaties, etc.

Diffferent specices have 100-fold differences in resistance. Evergreen trees are much more sensitive than deciduous. As for crops, onions are most sensitive, cereals and grain moderately, rice is most resistant.

There can be a 50-fold difference in resistance within a plant species according to the point in the growing season. Flower buds are much more sensitive than mature seeds, for exmaple. A crop might survive, but yield nothing for that year.

http://www.emedicine.com/emerg/topic898.htm
http://www.emedicine.com/Emerg/topic899.htm

In a late 1950's setting, both the G-series non-persistant and V-series persistant agents would be avalible. The G's were synthesized in the 30's and 40's, and VX in 54. Those links contain symptoms, emergency treatments, etc.

The novel is finished but I am now filling in details, the sites are great---I see great pages coming out of them.