Show Root Categories Alphabetically

Show Root Categories Alphabetically

<?php
$cats = Mage::getModel('catalog/category')->load(3)->getChildren();
$catIds = explode(',',$cats);

$categories = array();
foreach($catIds as $catId) {
       $category = Mage::getModel('catalog/category')->load($catId); 
       $categories[$category->getName()] = $category->getId();
}
ksort($categories, SORT_STRING);
?>

 <select class="input-text " id="partner_cats" name="partner_cats[]" title="partner_cats" style="height:20%;" multiple>
                                     <?php foreach($categories as $name): ?>     
                                            <?php $cat = Mage::getModel('catalog/category');
                                             $cat->load($name); ?>
                                                  <option value="<?php echo $name; ?>"><?php echo $cat->getName(); ?></option>
                                      <?php endforeach; ?>
                                        </select>