The spring can be a tricky time in terms of knowing what to wear. You leave in the morning and its cold, but then the middle of the day is 60 degrees, but then around dusk the temps begin to plummet. Sometimes synthetic materials just don’t cut it, but don’t worry there is always wool. Smartwool has been expanding their selection of tops in recent years, and all that investment has paid off. I have been able to review a few of Smartwool’s 2013 offerings over the past few months and have been incredibly impressed. Read below for a breakdown of three various tops that will take your outdoor wardrobe to a new level.PhD Run Short Sleeve Top ($85)This short sleeve top ended up being my go to first layer through the winter, and over these past few weeks of warm weather (minus the snow days we recently received). The top is constructed of 79% wool and 21% nylon, the fit is superb, and has quite a few key features. Smartwool used a lighter weight knit texture in the usual problem areas, such as the back and underarms to allow heat to dissipate. I found this incredibly useful especially when layering up in the colder weather. Smartwool also constructed the shirt so that the seams for the sleeves are not under the underarms. As stated before chaffing is about the worst thing ever, so not having to worry about that is quite nice. The top is not a super thick weight wool, which made it great for layering, but also when the warm weather hit the top was great on its own. The fit was comfortable over long distances, and I didn’t find any annoying things that rear their head after mile 10 like on other garments I have tried. The Short Sleeve Top is one garment you should add to your stockpile this spring.PhD Run Zip T ($110)Spring is a fickle lady so while the middle of the day may be warm enough for short sleeves, the mornings and evenings can call for something a bit heftier. This is where the Run Zip T steps in with its long sleeves, and half zip. This top is lightweight and has many of the same features as the Short Sleeve Top such as the seamless construction, lighter weight knit texture in certain areas, and a sporty athletic fit. I ran with just this top on and it kept me quite warm, but is also great on top of another layer as well. I found myself layering up with something like the Short Sleeve Top below, and then the Run Zip T on top. The half zip is a great feature, because when the sun comes out you can release some heat without having to take the layer off. In addition to running, I also used this top a lot when mountain biking and hiking. It truly is a one of those garments that you seem to keep reaching for no matter what the activity.NTS Mid 250 Funnel Zip ($115)For those colder mornings and chillier evenings, be sure to get yourself this heavier weight top. Like the Run Zip T this top has a half zipper as well, flatlock seams, and a tailored fit. They fitted this top with shoulder panels to eliminate shoulder seams, and also gave it thumbholes so you can make sure the sleeves stay put. I used this top mainly for hiking and camping. I found it too heavy for running and never took it on a bike ride. It is incredibly warm with a tall collar and was the perfect campfire companion. I found it best to layer up underneath the top, and then wear a shell over it to cut the wind. Be sure to get this top to cut the chill during the early Spring season.