go through Ilex forest, enter Goldenrod city, Beat Whitney, then go north until you reach the park. Go to the north-east corner, and there's and entrance. Go down a little bit and you'll see a path to you're right. Beat the two trainers there, and talk to the girl who's next to the odd tree. After that, go back to Goldenrod, and enter the house that's right next to the gym. Talk to the lady in red, and she gives you a water bottle. Go back to the strange tree, press A in front of it, and you'll pour water on it. After you do that, it attacks you. It's a level 20 Sudowoodo, and you might wanna catch it, since this is the only opportunity to catch it in the game, so stock up on Great Balls.
You can only catch Vulpix in SoulSilver, not in HeartGold. You can catch it on route 36 and route 37.
Level 36.
Route 36-37
After catching/defeating sudowoodo a man on route 36 will give it to you
Route 1, 2, 29, 30, 31, National Park, Route 36, 37 and all at Night time.
in route 36 after you have defeted or captured sudowoodo
You can get the Hard Stone from Arthur, who is located on Route 36 on Thursdays.
Get school boy Alan's number (he's on route 36).
Talk to Alan the Schoolboy on route 36. Battle him and get his number. He is the one with the fire stones.
get the sprayduck from golden rod flower shop and water it.
the place is called Ruins of Alph. you can find it by going south from route 36 GOOD LUCK!!!
Sudowoodo is on Route 36. But there is only one, I can tell because I own the Crystal Version. It is at Level 20, but I don't know what Pokeballs you have...A wild question appeared!How_do_you_get_skiploom_and_jumpluff
Get schoolboy Alan's phone number on route 36
L.36
I went East out of the National Park, Into Route 36, then use the Squirtbottle on Sudowoodo, battle or catch it, then go Northwest and into Route 37, past 3 apricorn trees and past a gate. YAY.
Level 36.
in Pokemon soul silver you can find it at route 36 or route 35