Catawba rhododendron bushes can reach a height of 6'-8' with a spread of 4'-6'. Displays are most effective when rhododendron bushes are massed together. These are poisonous plants -- do not allow children to ingest any of the azaleas or rhododendrons.
Best Answer: Tornadoes are caused by winds. When a tornado forms the wind pressure around the tornado drops and that's what you see on the barometer, the pressure goes down.
This creates weather systems in both large regular systems of heat exchange and smaller systems where hot and cold air masses mix, producing chaotic processes difficult to predict with any accuracy. It is these latter, smaller systems which create tornadoes. A tornado occurs where hot and cold air masses mix. The hot, high-pressure air is attempting to rise. The cold, low-pressure air is attempting to sink. As these air masses pass each other, they form a vortex, a swirling maelstrom of air. If there is enough heat to drive this engine, this vortex can become temporarily stable -- a tornado. So long as there is heat to keep it going, the tornado will keep growing stronger until, eventually, the air masses have mixed sufficiently for the heat to dissipate.