show custom text field only when it's populated

Question

Having trouble with a custom field. It's a plain text field, called special_note.

<?php $specnote = $_product->getResource()->getAttribute('special_note');
  if ($specnote) {
    echo "<div id='specialnote'>".$specnote->getFrontend()->getValue($_product)."</div>";
  }
?>  

The specialnote div is always showing up, even when there's data. I've tried variations like if (!empty($specnote)) and if (!isnull($specnote)) to no avail.

How do I make is so that the div only shows up when it's been populated?

Additional info: this is in the file /app/design/frontend/mytheme/theme/template/catalog/product/view.phtml

Field is set up in magento as a 'text field' - and the settings "Visible on Product View Page on Front-end" and "Used in Product Listing" are both set to yes.