A state senator campaigning for the Nebraska flag to be redesigned has revealed the banner was displayed upside down for 10 days before anyone noticed.

Burke Harr, who represents the eighth district in Omaha, said the flag had been hoisted incorrectly on top of the Nebraska state capitol building.

“It took someone drawing it to my attention before it was changed,” Harr told the Nebraska state executive board on Monday, according to the Omaha World Herald.

Harr said the fact no one was able to tell that the Nebraska flag was upside down showed that the banner was ready for reform. He is sponsoring a resolution which would see the flag redesigned.

The current flag is essentially just the Nebraska state seal plonked on to a royal blue background. Critics have said the flag is crowded and hard to recognize.

Maryland’s state flag was ranked the worst on the website Thrillist. Nebraska was 49th. Photograph: Alamy Stock Photo

It depicts a blacksmith with a hammer, a steamboat on a river, a steam train chugging past some mountains, some trees, a little house, and the Nebraska state motto: “Equality before the law.” These items are enclosed in a double-ringed gold circle, which bears the words “Great seal of the state of Nebraska” and the date 1 March 1867.

“That’s fine for a state seal,” Harr said, “but a flag needs to be instantly identifiable.”

The Nebraska flag has consistently been ranked among the worst designed of the US flags.

Ted Kaye, who wrote a book on flag design called Good Flag, Bad Flag, put the flag bottom in his list of flags.

“Try identifying this flag when it’s up on a pole and flapping in the wind,” Kaye said to CNN, referring to the Nebraska state standard. Given the 10 days the flag spent upside down, it seems people might struggle.

The website Thrillist ranked the Nebraska flag 49th out of 50 states. (Maryland’s was ranked worst.)

New Mexico’s state flag, among the best. Photograph: selensergen/Getty Images/iStockphoto

“You don’t draw a guy in a robe trying to smash through a tree stump, you just don’t,” Thrillist wrote, apparently referring to the blacksmith shown on the flag.

In 2001 the North American Vexillogical Association ranked Nebraska’s flag as the 49th-poorest of all 50 states, and as the 71st-worst (out of 72) “subnational and territorial flags” in the US and Canada. NAVA found that Georgia had the worst flag. The state subsequently updated its flag in 2003.

Kaye wrote that a good flag “should be so simple that a child can draw it from memory”, should “never use writing of any kind or an organization’s seal” and should “be distinctive”. The Nebraska flag would appear to fail on all counts.

One problem is that there are quite a lot of state flags which feature some sort of symbol on a blue background. Montana, Kansas, South Dakota and Minnesota, which Kaye ranked 49th, 48th, 47th and 46th respectively, all share that design.

His favorite flag is New Mexico’s yellow and red pennant, which Kaye said recalled the state’s Spanish and Native American heritage, while he also praised the Texas and Arizona flags.